I'd suggest a one piece ABS Tony Dixon to start with, not too expensive, & plays quite well.
(You can often find them pre used cheaper, & they're easy to sanitize.)
Keyless flutes are easier, I find, almost as easy as whistle.
We're just about to go into full lock down again over here in the UK, (from what I've just been told); how long can we last like this?! 
The Kickbike really is just a big (foot) scooter, bigger wheels make it easier on rough ground, I used to ride my bikes (pedal cycles) off road quite a lot, a few years back........well, 20 odd years ago I guess it was now, doesn't seem that long ago.......I must be getting old.... 
Flat? - nowhere around here is flat, it's either up or down, & they're big ups & downs!
I had to walk up the hills when I was riding my bikes around here, so pushing a scooter up them is a bit easier, & I can get up to a fair speed on the less bumpy bits. 
Went for a quick walk last Friday, (about 6 miles), took just over the hour, & now I'm still recovering from it 2 days later.... 
I've been rather quiet lately, but I bought a bigger & better scooter with bigger wheels to handle the offroad side of my adventuring, (a Kickbike Cross Fix), but haven't really used it yet.
My whistling was on temporary hold, as I was trying to get my embouchure back on my flutes & piccolos; still somewhat hit & miss, unfortunately, so back to my low F, low G, & A whistles.
Still playing my harmonicas, (about as much as I was before).
Hope the trampolining is doing OK; I know it's getting hard to motivate oneself these days, with all the Covid restrictions, but hopefully, not for much longer.
Oh, how could I possibly pick just one..... 
It has been really quiet around where I live - until a couple of weeks ago - kids are back out playing, & noisy car stereos again, unfortunately! 
I've gained a new hobby whilst we were in lock down - I bought myself a 16" wheel kick scooter - it's really hard work at the moment on gravel fire road, but once I get used to it, I'm hoping to venture forth & put some miles in on it. 
Unfortunately, my playing is somewhat curtailed, as we have thin walls, & I don't want to annoy the neighbours - we will all be getting a bit stressful, 3 weeks in on our lock down. 
Stay in - stay safe.
I have several, Generation, Faedog, Tony Dixon, Waltons, Clarke, (told you you can't just have one).
Of these, my prefered high 'D' is a Tony Dixon tunable aluminium, but their cheaper one piece ABS comes a close second.
Welcome aboard the whistle merry-go--round.
(You can't just have one.....)
Seasons Greetings.......& may Santa leave you a new little friend....
Fear not, the Bb is on the extreme of normal holding & playing, you may need to use 'the piper's grip' on it & other lower whistles. Check out online videos to see how to use it. Basically, you use the pads of your fingers instead of your finger tips, put the pad of your ring finger on the lower hole, & let your others go where they want to go, same with the top three holes. It just takes a little bit of practice, we all need to use it on the low whistles.
It's nice to get a new whistle now & again. I have found that high priced whistles don't necessarily play any better, but it's nice to have them. You may find the sound of brass works better for some tunes. Our tastes do change over time, enjoy them both.
That sounds like a plan, Norman, any idea what type you'll be looking to get?
Well.......just ordered my Xmas present. 
Seydel Saxony orchestra tuned chromatic harmonica. Most of my harmonicas have ABS combs, but this one has an aluminium comb, so now I'm looking forward to seeing how different the tone will be.
I have a Gemeinhardt myself, but I don't really play it, I prefer keyless. Of those you list, the only other maker I know anything about is Selmer, they used to make good instruments.
If you have a music shop nearby, you may be able to get a refurbished flute, & advice into the bargain.
This forum is for the tin/penny whistle, so not many will have any knowledge of flutes, but you might like to try this other forum for better info - https://www.fluteland.com/board/
Most people start off with either a high D or high C, depending on the type of tunes you want to play.
A good book to help learn flute would be 'Flute for Dummies', (you could get a pre used copy quite cheaply from a second hand book store like Abe Books online).
If you haven't bought your flute yet, maybe consider a keyless 'simple system' flute, just has the 6 holes like a whistle.
P.S. Open or closed holes generally refers to Boehm flutes.
If the guitar isn't a pleasure any more, take a look at ukulele, lots of guitarists have taken to them.
Flutes are nice, but I've had difficulty in obtaining my embouchure, it comes & goes, but I keep trying. I now have a couple of nice keyless 'simple system' flutes (& piccolos) in my collection.
Hello, Gwen, I'm fairly new to whistles, my cleaning so far has been of pre used instruments, but I would think not very often, unless you are a wet blower.
None of mine have any indication of needing cleaning yet, nothing in the barrel or fipple. If you do see any build up, that would be the time to give them a clean.
I don't think small amounts of deposit would affect the quality of sound much, but it's nice to keep them looking good anyway.
Had a nice practice session yesterday, mainly my 'A', low 'G', & low 'F' whistles.
I'm beginning to get the 'feel' of my MK Kelpie low 'F' now, it has a lovely tone.
Seems to be a dearth of decent whistles on Ebay lately..........did I buy them all! 
Still look...just in case...though I don't need any more. 
Another, sometimes useful whistle forum.
Oh, I think I'm fairly well covered for plastic whistles...... I do have the Susato 'B' & the Dixon ABS low 'G'.... plus my Susato high 'Eb', Dixon ABS high 'D' & low 'D'.... so I think that I might just manage..... 
I do have 3x 'A' whistles, two of which I really like, & play often, (Dixon Trad brass & a Thunderbird aluminium), the other one, (Dixon tunable aluminium), has a bit of a quirk in that I seem to have to twist it slightly to get the second octave, so I really didn't need another - but I was tempted.
Hey......I resisted a Susato in 'A'.........my whistle aquisition syndrome seems to be curing itself...
Yep, it's definately a key of 'B', & quite a nice tone to it, after playing a couple of tunes on it.
A Susato advertised as a high 'D' on Ebay appears to actually be a 'B', looking at the photos - so at £23 (incl P&P), it's mine - I didn't have a 'B' whistle, but will have soon, methinks.
Yeah, I mainly play an 'A', low 'G', or low 'F' when practicing/playing, just occasionally bring out the big ones.
I've gone & done it again, an MK Kelpie low 'F' came up for sale, it will be added to my ever growing collection of better quality whistles.
So now I think I need to thin out the collection, the question is, should I try selling the Gens/Faedog/Waltons, or just find a charity to give them to.
I think I favour giving them to those who may not have the resources to buy them for themselves, or where they could be used by multiple students to learn on. (Will have to see if I can find such.)
If I post in this thread my whistle aquisition won't look so bad.
I really wasn't intending to buy any more, although I would have liked another low 'F'.....
Guess what - an MK Kelpie low 'F' just came up for sale - now these are the bees knees when it comes to whistles - so I just had to add it to my collection.
It was priced at two thirds list price, is one year old, & has been hardly played, by someone who has a low 'D' Kelpie, which s/he prefers to play in their limited available playing time.
Came across this website, really useful, lots of mainly old folk tunes.
Scarborough Fair & Greensleeves are my harmonica forum challenge this month, so I think I'll try to get Greensleeves onto my list, I know it's a bit passe, but I like it. 
I think I've come to the conclusion that the thicker walled whistles give the best tone.
My standard 'beginner' whistles, (Generations/Walton/Feadog), are OK, but my traditional brass, & my aluminium whistles have much better tone, & I find the polymers have a kind of softer/warmer tone to them too.
TD Trad brass high D piccolo arrived this morning, it plays well, & isn't at all shrill sounding, in fact, it has quite a nice tone.
Playing simple system flutes, whistles, & piccolos isn't that hard to do actually, that's probably the reason I get on with them so well. 
I still like to try new things out - if at the right price.
An opportunity to buy/try a Susato Eb at a reasonable price (£19) has come up , it has been lying around the dealers for a couple of years, evidently, so I ordered it, this will be my first Susato.
I also came across a brand new Tony Dixon TRAD brass high D piccolo, going fairly cheaply too, (including postage £18.19).
I do like to play & switch between them often, as it keeps my interest up - also my harmonicas, between chromatics & tremolos.
I do like this music hobby.
Good for you, Larry, I hope it works out OK, I used to like mine, it was just a bit too quiet for me.
Decided to try out a (cheap) bamboo Chinese Dizi - it arrived with some 'membrane' in a packet, no idea what it was meant for, but there seemed to be one too many holes, so I taped it up, & now I have a spare bamboo flute in 'F'.
I have been having a good time with my M&E 'F' flute this past 2 days, seemed to get the embouchure just right, on some easy tunes.
(Have also been playing my 'A' & low 'D' whistles.)
I have a feeling that may be due to the prevalence of wound strings on guitars, my ukes have fluorocarbon strings in the main - but I will also be trying it out on my steel string electric uke, with the effects that are on my amp.
Funnily enough, I've just bought a glass slide for my ukes, I'd been been meaning to get one for ages, (about a year actually).
Thought I'd try multi tracking a tune using 3 different whistles.
Shall We Gather at the River using 3 different whistles
ShallWeGather3.mp3 - 896KB