Hiya,
There are 2 PFCs for the Altezza (4 if you count the late model ones) but 2 meaning, one for Turbo/Boosted engine, and one for N/A setup.
Brash Boys are very handy with the PFC, especially when it comes to making it work with the 5AT. The PFC is probably the best mods you can do on the BEAMS engine. You can tuned the VVTI cams far better than the Camcon allows you to, enabling you to adj both INT/EXH Cams, unlike the single cam the Camcon does. Ontop of that it disengages the E-Throttle so the response feels much better.
I've seen Dyno results of gains as big as 35HP+ from a PFC and mapping.
I had a obscure accident on my last motor which led to me rebuilding the motor, then it needing a head gasket change after 3000miles, then just swapping out the engine for a new low mileage unit. Now the new parts have run in some (clutch mainly) its all good to go!