30 is best for the pothole riddled asphalt & concrete they call roads around here. When I would chance anything with less profile, I found my cadence would suffer as well as my enjoyment of riding due to safeguarding my rims. The puncture resistance & wet performance with low temp traction is what keeps me attracted to the Pirelli P Zero Race/P7 tires. They tend to wear faster in higher temps (80F+ ) , but still perform good. The best puncture resistance experience I've had was when I had no choice but to run over a broken bottle bottom & the tire maintained itself. Once the tire is past the 75% usage point, it starts to become a walmart latex tube that was returned & restocked.
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