I would have to agree because in a straight line run my V11 with 11:1 pistons isn't signifigantly faster than ones without ( and with similar mods - PCIII, Exhaust).
However!
I know for certain riding against the same bikes that I have a HUGE increase in midrange power - as anyone who knows what increased compression changes will do for a bike. Higher compression has never been a way to more horsepower. It is a way to more efficiency. It is probably the best way to increase fuel efficiency.
It also makes the bike much more fun to ride - as in "seat of the pants".
I will reccomend it to anyone!
P.S. I would like to hear how Al's Mike Rich kit works out. My FBF pistons were such an easy job to install. I cannot imagine why everyone else has not done it yet!!