I think my Carbony mezzo G whistle is a bit of a prima donna. It can sound beautiful, but needs constant attention to achieve low notes (blowing it out multiple times in one hour of practice, cleaning it every 3 days). Does anyone else have this problem, either with a Carbony or other low G whistles?
I can’t speak for Carbony whistles (except that IMO they are vastly overrated, I’ve tried a good few but I don’t own one), but my original Overton low G is my all-time favourite whistle,as stable as a rock - so it’s definitely not a problem of low G but of your particular instrument.
My only mezzo G – Kerry Busker – is fine. Loud, as you’d expect, but very uncomplicated to play.