I would go with the Fuji 1.9 or Diamondback, if you decided to go with Performance. For resale value, the Fuji would be nice because somebody new to biking would see disc brakes and be willing to pay a premium on it, whether they are worth it or not (I did... not sure it was worth it yet, but I do like adjusting disc brakes a lot more than linear pull). I think it would be more enjoyable if you ever wanted to go out for pleasure rides as well.

I was in your shoes last year- hadn't ridden much since high school and decided to start biking to save money and weight. I rode a couple practice runs on a friends bike on the weekends just to see if I would be up to it before I decided to purchase a bike. I read a lot of forums about how one should conduct themselves on a bike while sharing the road with cars (and, in my case, a lot of semis since I work in the industrial section of town). I learned that there are a lot of varying opinion on what is the safest way to do it. The best advice is just to do what is most comfortable to you. And buy a mirror. A lot of "roadies" think mirrors are dumb, but I think mine has saved my life (or at least my limbs) a couple times by being able to see the semi swinging wide behind to turn. I also almost always act like a car (i.e. not running red lights, claiming the lane for left turns and when there isn't a bike lane). I never ride on the sidewalks. And after reading a lot and practicing, I am now almost full-time bike commuting (I still have to get groceries with the car one day a week). I have a 7 miles one-way commute, so similar to you. A year later I have a lot more confidence on the road and love my commute. I hope you do as well.