Angel Silent Piston/Cylinder Head Set questions

[sAfuRos]

I probably should have made one thread instead of the other thread too but i digress

I ordered an Angel Silent set on a whim (excited to have the opportunity)
However, i run a P90 (ver 6). That means that the cylinder head is non-compatible, obviously

So, if i run the piston head alone (which, thankfully is the silencing part), would i be ok with a sorbo pad as well?

Also, i've read around that Angel silent set's are meant for lower FPS set ups. Can anyone confirm this? I'm planning on making my P90 as silent as possible and a semi-automatic for stealth-ish purposes. I wanted to have a higher FPS, however, around 380. I want the angel set to last quite long given its rarity, so would 380 be too high?

I could just move down to 340ish and then i'd be able to do a TK twist barrel as well, which is a benefit i suppose

Thanks, you guys are way faster/more knowledgeable than other sites o.O