MercBezerk

Speaking from experience, the Viper is a kick *** car. It's got all the sex appeal, gawk command, and raw guts anyone could ever ask for. The trick of it is this; how well do you like your spline? The Viper rides like the proverbial rock. It shakes, gitters, rattles, and basically sounds like it's breaking the sound bearier over any surface less smooth than a glass tabletop. Also, something to consider for your girlfriend who you've not been in the back seat of the Benz with, it's EXTREMELY hard to get in and out of Vipers. Your woman will hate it after a few rides, trust me on this one. Another thing to consider, the Merc will always be there to help out in weird situations, i.e. wet/oily surfaces, sharp curves that might demand a bit more attention, etc. The Benz will help all it can, even with the most inexperienced drivers. The Viper will not. In fact, the Viper is more apt to help you screw up. Remember also that you are a student...what's the jealously factor like at school? I assume that if your AMG is ok that the Viper should be too. But, most people can't tell the differance between a regular Merc and an AMG. Also, remember the resale. While the value might be on the side of the Viper in a few years, how many people are inclined to buy one? Fewer than the Benz, mark my words.
So in choosing, take your time, and consider every concievable factor that goes into your driving. My personal idea? Bid farewell to the AMG, get the Viper, and pick up an Acura for a daily.