I have an F# key but I still use the left hand split F with the right hand Bb side key. It’s just easier. Both of them seem to sound pretty much the same.
I have a Martin Comm3 and do what Mike Potter does, have to lip it up a bit. On my Buffet SDA I do that and add the RH1. On my Purple Martin Indiana, which does not get much playing time these days (fails to hold adjustment and I dont’ want to sink a lot of cash into it) I can do the Split F and Bb side key, or the 1 and 1 speaks well, as does the Split F, Side Bb and RH1
Altissimo G escapes me, I don’t play much up there. 😉