My $0.02.. i had way better flat protection with my slicks. since they had no cutaway parts, the whole width of the tire had thick rubber on it. never ever had a flat with my slicks. and i took them offroad a lot, even on trails littered with blackberry bushes and no problems. i didn't like spinning out on mud and wet grass so i have semi slicks on now, still only 1 or 2 flats in 300 miles through the same type of abuse. i have the "chevron tread" i think it's called. where the tread makes a V pointing down if you're looking at the front of the tire. the continuous line of tread down the middle gives you good smoothness/efficiency/wear when the tires are pumped up fully. if i let out 20 psi then the tread on the side comes into play and is quite stable off road as well.