well you wouldnt lose power with a fmic, but you would increase lag a little during the times when the rpms are above the normal spool level (ie, you let off at and get back on it at 4000 rpms going through an auto-x corner, they're be an extra split second of lag because of all the extra air in the long charge pipes). it isn't really needed with your setup though, and a tmic would be easier to do, assuming you could find the right one. a usdm wrx tmic could fit snugly in if you modify it a little bit to fit between the intake mani and firewall. the other problem with that setup is finding/making the proper piping between the turbo and tmic. you dont need a fmic until you're up over 400hp.