Excellent points Indysteel, thanks. Yes I tend to over think EVERYthing, lol. I'm satisfied with my choice this time based on the fit in my test rides. The only advantage to switching out the tires right away is I get a big discount, if I wait I have to pay and extra $150 when the time comes. But you're right, for my purposes I probably will be fine with the tires the Jett comes with. I'm going to be riding with a bunch of people on 26ers and was just thinking that if the lighter tires help you get up the hill faster (the one sticking point of this 29er is supposed sluggish starting up hills), changing the tires out would help me keep up. Anyway, yes I am way over-thinking, maybe time to just drop it for now and figure out things as I ride and get accustomed etc.