ECU as in aftermarket? If so then I would say you should get the PFC. Make sure that you search and learn as much about it as possible. Also, when planning for your purchase, DO NOT overlook the price it takes to get it properly tuned. I would guess that you are looking at around $400-$1000 dollars for a tune depending on how good of a tune you want. Also, unless you are near a power excel shop, you will want to purchase a datalogit. Your tuner can use it to tune the PFC and it is MUCH better than the commander. You can get everything that you need from monkeywrenchracing.com. Good luck.
friend just read the lastest Option mag and told me, Japanese best ECUs are: 1) HKS FCON V PRO, 2) Apex Power FC, 3) some piggy back ECU that i forgot the name of :gap: , 4) TOM's something ECU 5) Greddy/Trust Emanage. MoTec wasnt in there, but we're thinking Option was only rating their products.
apexi pfc is probably the best route. not cheap (a little over $1,000) but worth it if you have performance aftermarket mods done and want to take full advantage of them. the people i've talked to with this loved it and helped improve their track times quite noticeably.
i havn't really heard anything about the f-con vpro but trial japan does a lot of testing with it...if thats worth anything to you