initially cost....but then upon doing more research...I found out....20 x 20 points is overkill for what I am doing 16x16 (emanage) was good enough as I am keeping stock turbo....FMIC and using 9psi for daily driven car.
If you're going bigger injectors, turbo and all out top end peak power...then yeah by all means, go PFC, the resolution is higher for you to squeeeeeeeeeze every pony you possibly can to hit your peak power figure @ 7,000rpm (eg)....but me...i just want quick spool up and lots of torque on the stock turbo to get me off the line quick