1) I actually have no idea what that key does functionally, I'm still new to this layout also

2) If you mean replacement keysets for ALPS switches, there are a few vintage ones but nothing that's really made aftermarket today. SP has the molds, but I don't think a full keyset has been made recently.

3) Not sure

4) The only switch comparable in terms of MX is blues. Not really the same at all though. The White XMs are a tad louder, but not as high pitched. The switch also seems a little snappier than Blues, and maybe a tad heavier but I don't actually know the actuation force or anything. Still new to ALPS myself.



Maybe someone else can comment on White XMs better than me though =)