I have that bike (01 XR800). I have had it two yrs now, and have about 2500 miles on it. I bought it as a commuter bike and it hasn't let me down. Have done light trails, small hops, MS150s, metric centuries on the road. Overall, I love the bike! I keep conti GP3s on it about 2/3 of the time, and when I get bored with fast road riding, I put the green 'cross tires back on.. I love being able to switch.
However, it has one weakness: The wheelset was CRAP! I would not go off-roading (or anything but very light trail riding) with those stock CXP-21s which were (in my opinion) rather poorly built with spokes that are too light. My rear wheel constantly gave me problems, going out of true, and after 1500 miles popping spokes (both drive and non-drive side). By the way, I am bigger (6' 3"), and weigh 170#.
About 6 mos ago I broke down, ordered a Mavic OpenPro rim, and had the best guy in town build me a tough rear wheel with 14/15 gauge spokes, extra spoke "washers" around the hub, and tied/soldered crosses... I've been happy ever since.
The only other thing that I'd note is the price is way too high. Note that I bought my bike 2 yrs ago.. I paid the same price as you, and had a set of Time pedals (~$120) thrown in for free. If the bike is still new, its been sitting in the bike shop's inventory for a couple of yrs now and they should be motivated to get rid of it. Use that, and the crappy wheels, as negotiators... maybe talk them into a better wheelset for the same $ (from now on, I won't buy any wheel that wasn't hand-built!), pedals, etc...