Can't say too much about section 517. They were in the upper level corner which is a pretty boring and cost efficient place to sit. We were watching the Ravens play the Cincinnati Bengals. The club level at M&T Bank is small enough that it doesn't really effect the upper levels. So it still feels somewhat like the 2nd level. Stay away from the rows in the "20s" as those sit at the top. Seats are cramped together pretty good, you should purchase club seats if having a lot of space at your seats is important to you. ($200+ per ticket most games).
The easiest and cheapest way to get to the stadium is always via the MTA light rail system. Parking in downtown Baltimore has become more expensive and harder to come by with the building of the casino downtown. If you're hungry before the game, you can check out the Ravenswalk which is an outdoor tailgate with live music and games. It's on the walkway between M&T Bank and Camden Yards (the baseball stadium). If you're more in the mood for a sit down bar or restaurant, you can't go wrong with Tommy's Tavern or the "Tilted Pig". Both are within close walking distance of the stadium.