I’d also vote for low (alto) G, for reasons given above, that it’s useful to have that slightly lower range than the high D, and that you can play in G, Emin, C, Amin, D & Dmin - a pretty useful bunch of keys, though now I think of it, I don’t think I’ve ever used it to play in Dmin.
An extra reason would be playing harmony lines under the lead. I actually use the alto G mostly for this, either playing second in a duo with my wife, or as part of a quartet.
But it also comes in at the local pub session, where if I get bored with oft-repeated tunes on the high D (or if there’s half a dozen other high-end wind instruments anyway), I can switch to the G for a different sound and different fingering for the same tune. It’s now my preferred whistle for ‘Bear Dance’, ‘Horses Brawl’, & a couple of others, and that gives the D a rest.
For all the above reasons, my next most often used whistle is the A.
That’s really sad to hear. Might I suggest a change to a different low G, and maybe other C&F members could advise? I can’t really help with a recommendation, as both my low Gs are home-made.
A good low G is surely a likeable whistle.
Interesting. So it might be useful for me to try making a bass G body for my bass A whistle? My next key is either going to be Bb or G…
What whistle key to purchase next really depends on what you’ll be using it for.
At most traditional Irish sessions 99% of the music played can be played on a D whistle. If there are Irish fluteplayers and/or uilleann pipers there 100% of what they play can be played on a D whistle. (This is assuming that they’re playing flutes and pipes in D.)
When you get those darn fiddlers, boxplayers, and banjo players together (sort of a Critical Mass thing) they tend to start playing tunes that are very difficult/practically impossible on a D whistle.
For these situations it’s very handy to have a C whistle, when these people launch into a string of tunes in D minor and G minor (and sometimes C Major and F Major). You finger like you’re playing in E minor and it comes out in D minor, and so forth.
Also handy in an E whistle for when they play an extended set in A Major, with tunes with G#'s all over the place. (You just finger like you’re playing in G and it comes out in A).
Now that’s at trad sessions.
If you’re playing on your own obviously you can play on any key whistle you like.
For church gigs etc you might end up with a large number of whistles to handle all the keys the group plays in. I had a church concert gig where everything they did worked on either a D or C whistle. At another gig I used only an E and Eb whistle.
I’ve used a G to play in D minor, the reason being that I’ve sometimes played with fiddlers or accordionists who play tunes which are usually in A minor down a fifth in D minor, tunes such as The Gravel Walk.
With a Low G whistle I can finger then in A minor as usual but they come out in D minor.
All that stuff is about keys.
Then there’s stuff about range. Fiddlers, boxplayers, and banjo players will play some tunes like Tam Linn, The Dawn, The Bear Reel, and so forth that dwell below a D whistle’s range, and tunes like that can be played on Low G or Low A whistles. Then you can play the full range of the tune with all the notes in the proper octave. But trad players usually don’t do that, but play them on a D whistle with octave substitutions.
It’s a Susato Kildare. Sounds like a goose being strangled. I’d love to change it, but since spending a huge whack of money on a new accordion, I’m not allowing myself any new whistles - instead I’m waiting for Mr Husband to start making them for me. It could take a while.
Did you happen to try the Susato O-Ring Tweak?
https://forums.chiffandfipple.com/t/mtguru-o-ring-susato-tweak/47141/1
I don’t go to sessions much, but I find the low A more useful in my playing than a low G. Different strokes for different folks. It lets me play all those D tunes that go below D without problem, and adds A and associated modes to what I have available.
Thanks, I hadn’t. On that topic, MTGuru says Now if you loathe your Susato, this tweak won’t turn it into your favorite whistle, so it may not achieve much, but it’s worth a try!
Alternatively, if anyone out there has a low G Dixon they want to swap…
Wanna sell it?
nope, I love my dixon G 
I should really post a clip of my Susato G:
Oops, that didn’t work. Better try again …
I do, but I need to get another low G in its place, and the Dixons are much more expensive.
the polymer G is £35 from the Dixon website, the metal one is £62.65 - the susatos are, I think, more than that?
You’re right, the Susato is £45; I didn’t make it clear that I want a metal Dixon. And of course I couldn’t ask full whack for a 2nd hand Susato. However, if Hoopy Mike makes me an attractive offer I might just take him up on it. 
Hmmmm. Looks like I’m too late. I’m after a mezzo G at the moment. I can’t decide on a cheap Dixon poly (just in case I don’t get on with it and end up paying for an expensive one as well) or saving for a Chieftain or Goldie. Decisions, decisions. 
I like my Dixon poly a lot, if that helps.
I have a Dixon Trad and a Dixon poly low D. I like them both but they’re just too quiet for sessions. 
Hmm - I’d like a low G, but how much is a second-hand Susato that sounds like a strangled goose worth? I do have a theory that 99% of whistles can be made to sound lovely in the right hands (not that I’m saying that my hands are the right ones for this whistle!)