sunstorm

I've been commuting 1-2 days a week on a Trek 7100 WSD for the past two years (bouth used but hardly touched for $50). One way is 6.5 miles in medium to heavy traffic with a couple 7% grade climbs, one of which I can't actually complete without walking the bike. Bike weighs in at 48 pounds without panniers. I carry another 30-40lbs in books, computer, clothing, etc (I'm a med student.) With my time getting slimmer, I want to fit in more commuting for fitness and stress relief, and I think it is time to upgrade.

I tried a Schwinn Tailwind Ebike and despised it (top heavy, uncomfortable, etc.) I headed back to my LBS to check out some Treks. I like Trek as a brand, and I generally love the LBS guys, who do a great job helping me learn about maintaining and handling my original bike and learning to handle road traffic and plot routes. I tried a 7.3 FX Disc, a 7.5 FX WSD, and a Utopia. The Utopia didn't fit me (the effective top tube length was just a bit too long.) The guy that was helping me wants me to try a Neko, but they need to build one in my size (which seems to be taking far too long, three days now.)

I like the FX's, but they feel a bit squirrly to me (guy at the shops said that is because I have been riding such heavy bikes.) I am not sure I understand the differences (advantages/disadvantages) of the 7.3 FX Disc vs a 7.5 FX WSD (the 7.5 Disc is beyond my budget) and I can't find anything online that really reviews the Neko. My commute is all road way or paved bike trail and parking lots.

I'm also not sure what is important to consider for this commute; weight, disc brakes, hydraulic fork, WSD? Also, I would want to use this bike for casual errands, paved green way riding, and possibly group rides. There is a gravel driveway I might need to navigate occasionally.

Suggestions? Opinions? Thanks in advance!