Just started the tin whistle (simultaneously with the Uilleann pipes…), and have a Walton whistle in D. Just received (bought from eBay) a Clarke C whistle, silver colored w/wooden fipple plug. Can’t believe how much easier the Clarke is to finger, and how much nicer it sounds.
I love Waltons, send it to me and I’ll give it a good home. 
Try tweaking it first. The head pulled off mine without needing to heat it, and I cleaned out the fiddly bits of plastic swarf left over from the manufacturing process. Then I filled in the space under the windway with modeler’s putty (auto body putty to others), and that helps. And yes, I know about fumes, etc from body putty.
Anyway, you might try a simple tweak or to first.
With best regards,
Steve Mack
Sure, you can have all the Walton’s you want, as far as I’m concerned.
worst whistle I ever played, snickered evilly as I tweaked it to death, then threw it in the garbage…
hehehe
M
(I could be a bit odd, the above is my opinion only, and shouldn’t be construed to mean that these are not good whistles in general, just that I specifically don’t like them. See, others think they are just grand!) 
Let’s keep this in perspective shall we: the GoldenTone Walton C is the very finest whistle value in creation and the MellowTone D ain’t bad either..hmmmmph
Philo
I like Walton’s Mello-D’s a lot, though sometimes the tuning is off and the bell note is sharp.
If you can find one that’s well in tune, you can really lean into and push these whistles and they sound great played that way.
The narrow bore brass Waltons is a decent basic whistle. It’s not a particularly easy player–but it’s not the hardest whistle to play on the block, either, and it has great chiff popping through, if you like that. Only the chiffiest Generations have more chiff than this whistle.
The Guinness and the Little Black Whistle are both little squeakers. They benefit from carefully cleaning up the molding flash, but I find the tone thin and grating. Some people doubtlessly love it, but it’s not my cup of tea.
My Guinness is a very special whistle to me because my wife Shannon and I worked together on it for several hours. We cut away the blade and completely replaced it with a blade made of superglue, which was then carefully shaped and smoothed. It’s now a phenomenally good whistle, but because of the time and amount of work involved I don’t ever expect this to be a popular tweak.
That’s my take on Walton whistles.
–James