Anybody here running a ej257 shortblock with stock wrx heads? I've heard good things about the tq gains. Is the installation fairly easy as far as everything bolting up? Overall, how much WHP/ WTQ could i expect from putting on a stock 2.5 shortblock onto my 02 wrx stg. 4 (Utec, VF22, pinks, etc) with a good tune? Would upgrading to RA gears be sufficient enough or would i have to look out for an sti 6-speed?

*feel free to mention any other important notes regarding the swap.