I've had the Gintani ecu tune for several months now and have put the car thru it's paces with hard track days, etc. No issues here so far. Made nice linear but more importantly SAFE power. Heres my dyno chart from EAS. Steve at EAS told me the AFR, etc is very healthy range and safe for track. He also mentioned how it was one of the stronger cars hes dyno for the mods it has (test pipe + tune + 91)
http://www.m3post.com/forums/showpos...9&postcount=23
I don't have a dog in the race, just presenting my own experiences and 2 cents.