If orchestra Evah's tuned down a semi-tone are great, then maybe you'd be lucky with Evah Weichs?
I have both regular and solo Perms and they're quite different.
The A (B in the solo set) in particular is totally different.
Personnally I find the bottom Perms (A&E) too muddy and undefined, at least in the regular set).
I don't recall exactly what went wrong with the F# tuned at orchestra pitch.
It came off too quickly to remember!
I'd be more inclined toward solo Spiros than solo Perms, but that's just me.