Thanks everyone for the info provided in this thread. I just sealed the deal on a clean 2003 X495 w/ 54" deck.
I walked into the local dealer with a budget of $3500 and ended up with 3 to pick from:
1. 2011 X320 w/ 54" deck, 0 hrs, $3,700
2. 2008 X540 w/ 54" deck, 242 hrs, $3,500
3. 2003 X495 w/ 54" deck, 1000 hrs, $3,500
I drove all 3 and felt the X495 was the best deal for the money in the long run given it's versatility and the diesel engine. There was no comparison between the X320/X540 and the X495 as the ride quality and power of the diesel was in a class of its own.