Well, you will get better response in the MTB forum. We tend to get snobby in here. On that note I'll help what I can. I've spent some time looking at Urban bikes, they look like a blast, something to beat the sh*t out of. Personally, with something that is looking to take a beating, single speed is better. The simpler the bike, the less it will break down. At 6 foot, a medium frame is pushing it if you have long legs, but I'm the same height/weight with a 32" inseam and would go with a medium anyway. But on the note of standard features on the bikes, the gear set-up has better stuff. The DJ-1 is a better fork, and the gears could easily be stripped later if you decided against them. All in all, the geared one is a better choice (if you can find a medium)