Jeans, because I don't want to look like a cargo pants dork.
Also, with a 28" inseam, every pair of non-tailored pants make me look like a slob. By contrast, a pair of slim-fit (not skinny) jeans in selvedge denim fit me effectively perfectly, still stretch, but do not tear or hole easily. That's because selvedge = self edge. And that type of denim does not require a closing stitch to keep from unraveling, they're the original form of ripstop.
I buy mine from Uniqlo (Japanese fashion company), they typically run $50-60 bucks a pair, and are 98% selvedge denim and
2% spandex, which gives me that stretch. A single pair lasts me effectively 9-12 months of daily wear. I've been wearing them for 5+ years now and I still have my original pair, but they now have a holey crotch, so I use them for garage/grease monkey work. I have I guess four 'retired' pairs now. Also, Uniqlo offers inseam tailoring for an extra 5-bucks, so you don't have to roll your jeans if you don't want to.
For me the big thing is...crotch fit. Cargo pants, painters pants, hell 98% of pants are made to have a crotch that goes almost to my knees. I have big balls (
), but I don't need crotch room to my knees.