Probably not....just feels that way because now you hear it more you ride it harder ;-) If anything (and please peeps correct me if I am wrong) you'll loose back pressure which will effect performance...?
Not likely. Probably performs less well in non WOT operation to boot. Typically when sporties are run with wide open pipes their performance decreases in mid throttle application, but WOT will probably be about the same. If this is an EFI bike, WOT might be worse off as well. If you're happy though, who gives a *****?