Wheels, I'm really, really tough on ALL tapes and glues. Really, I've tried them all, and ST-30 has been, by far, the best.

I think one of the reasons is that I exercise a lot. I'm an athlete, so my syrup has to endure several hours of hot, sweaty conditions every other day. Not to mention, I think I naturally sweat glue remover!!!

But yes, I have noticed that the tape can turn white, but for me, that's when it's on its last, last legs. (Note that I usually get holds for 3-4 days in the summer and 5-6 days in the fall/winter.) And the ST-30 doesn't turn white until I have that weak-feeling adhesion coupled with a hot shower (w/shampoo and conditioner).

I don't know how long your holds are, but if it's turning white on you, then, like I've found (although I never let it get that far gone), that might mean that it's time to remove/clean/retape.