I'm looking at a Trek 1000 on CL listed for $400. I've been searching for a bike and think I want something more upright as I'm not sure my arms and shoulders will take the roadie posture. The bike is my size, however, and I'm having trouble finding something large (58 cm) and I'm thinking of trying it. My question is if I find the posture too aggressive what would it cost to make the riding a little more upright? Would simply a longer stem help much? I'm 6'2", 230 lb. I'm kind of a noob right now but I'm thinking down the road I'm going to want a comfort bike for riding with the wife and a road bike for organized rides.