but, if it were something like shocks/bars, it'd be easy to tell first look if they're the real thing or not (usually). but u just can't tell ecu from the looks of it and it costs a bundle. easiest way to actually tell is to go get a boost gauge or get on a dyno; "butt-dyno" =) simply isn't all that accurate. u could also try getting a g-tech, run a few b4 using new ecu, run a few after using new ecu, all in the same day/condition, and compare the numbers.