Oh cool that's really good to know now
um it runs amazing, I'm the second owner and it still runs perfect on the stock inners minus the barrel. Shoots so accurately almost to the same level as a m4.
I suggest the KS or Echo1 if you want a good all round gun for outer and internals
TM for great/outstanding/the best internals
CA Proline (clearsoft and the Original full black) if you want a brand new P90 since its canadian legal now since the upper receiver is made transparent. Still has a great feel and it has a good set of inners, including a very accurate inner barrel to use with the silencer.
Anything else I suggest you stay away like Well.
Prices range at $400+
It really comes down to if you want a used or brand new though and what your looking for in the gun/ what's available in the classifieds haha
Good luck!!!!