Seems like an ok price. I just bought an '05 R/T for 15.1k out the door, only 20k miles. When I was looking everyone recommended the R/T. There is a huge difference in power and a little difference in gas mileage. The SXT gets 17-18 city 23-24 highway, R/T gets 15-17 city 25-26 highway and murders most other vehicles on the road.
But it has been a great car so far. It is quiet, smooth, and well-built. Also handles like a midsize car which I didn't expect. I think they peak at around 38 Hz so find a good 15" or 2 with a low tuned box and the audio will sound killer. I'm working a 32 Hz box for my Brahma 15" right now.