My main concern is comfort not necessarily weight of the bike or disk brakes. I'm already very in shape, just looking to add some extra "cardio" to my day and figured why not bike? I just want something that will last a long time if well maintained and nothing cheap. I looked at the Urban X and I am just so confused as to what would be best. Lol. I don't necessarily need fenders but would want a rack for my belongings needed for work so that's a must. Is the 7.4 and 7.5 worth the extra cash to fork out?