I hear a lot of "it will create more lag because of more volume."
In theory that is true; however I can tell you that from my new setup on the stock turbo FFIM/FMIC/3 INCh hard pipes/90 MM TB, again i said STOCK turbo. The car feels much quicker for the throttle response; boost hits almost 400 RPM's sooner than before, and now in hot weather the car/pipes aren't heatsoked and eating up the power; it's always there.
So take what you want from that.. But all I know is the car spools faster.. Maybe because of less pressure loss because of the 32/12/3 IC, I think i read somewhere that the stock IC has like 3 psi drop @ 10 lbs? So when you hit 10 lbs on the stock IC it's really 13.. On my IC it's like 1psi drop @ 40 psi or something.. so .25 psi per 10 psi.. MUCH more efficient.