FMFs are not bad pipes for the last time. i have one. im not trying to get rid of it.
it depends on your mods. if you have a pretty stock motor, and you want to wake it up get an FMF. you cant beat their used price. look on ebay or on the forum. i think there is a memeber selling one for like $100.00 shipped.
if you plan to mod your motor alot (stroker, port and polish, big bore) then get the F7, LRD, CPI, or Power Pros. its really up to you bro.