I've also found higher psi gives more bounce on the vorti's. I think people are ramping up the pressure to compensate for the softer side wall but I don't mind the more progressive feel that provides. I'm running 30psi cold and find that just fine (i don't track the car)More good data / reviews coming in on these - thanks.
I have run between 30psi and 34psi and found more 'bounce' at the higher psi.
Fast road use at the moment, the temps seem to rise from around 30/31 to 35/37