I'd take that Jamis Dragon, SWEEET ride. The reynold steel will take away any road buzz and also the high frequency buzz off road. The steel frame will be about 1.3lbs heavier then a light weight Alum in the same size. You won't feel the weight too much when you get it rolling.
Good thing about the 29er is you can run the fatter knobby 2.25 tires for real dirt rides or throw on some 700c x 28-36mm wide tires for the street, Slicks or higher roller CX treads in those sizes.
If you pick the 29er, pick its size by riding it,
not the stand over with both feet flat. By design to keep the wheel base tights, it will be close touching your nuts to the top tube..
Youcan even go monster cross w/ it too
http://forums.mtbr.com/29er-bikes/i-...ss-355649.html