[MetroMPG]

I suspect the effect of pressure on straight line braking performance is less significant than the effect of tire pressure on handling. Just guessing, but I wouldn't expect to see much of a difference in straight line braking performance from 35-55 psi.

Unfortunately, it's harder to quantify "handling" effects for the purposes of a test.

Then there's loose surface driving. i'd say that higher pressures are going to reduce traction on gravel.