Just want to hit a couple points. Low end components have been disparaged a bit in this thread. Just for a counter point, I have a Sora front and rear derailleur on my bike and they have nearly 7000 miles on them with no issue. Some of the low-end Shimano stuff either road or mountain is quite durable in the long run. It's just that it's not the lightest stuff, but then if you're riding a bike with racks, fenders, and panniers, why are you gram counting? The other point I wanted to make was that interrupter levers can indeed be added to any bike that doesn't already come with them. However, you have to realize that there is currently only one brand of levers that will work with V-brakes and mechanical pull disc brakes, and those are the Paul cross levers. Regular cross levers only pull enough cable to work with caliper or cantilever brakes. Be sure which levers you buy if you go this route. Be warned also that the Paul levers cost $100, whereas you can pick up Tektro cross levers for calipers and cantis for as little as $15.