OK, I'm going to jump in here with a specific question about Bestop sailcloth vs. Bestop twill. This would be a replacement top on my '99 SE and also for a '12 JKU.
The SE spends significant time on tight trails. The top gets rubbed on brush often. Sailcloth or twill? Why? The JKU doesn't spend a lot of time on tight trails, but does go off road. Same questions.
The Twill is more "cloth-like". So imagine walking in the woods, and a branch getting caught into your t-shirt. It would be like that, but the Twill a little tougher than the fabric on your shirt.
The sail-cloth would be more acceptable to abuse. But the Twill is thicker, quieter, keeps the cab warmer and cooler. Plus looks a heck of a lot better.