Tom -
I have a 6284, haven't put many hours on it but overall a very nice machine and should fit right into what you're doing.
Cub had a fire sale on these machines before switching over to Cub Cadet Yanmar in 2008, so you can find some deals on em, many of them went to auction to clear the books. For the guys that bought them at retail, they will probably lose a few more bucks if/when they try to sell them. The "liquidated" machines will typically have the serial # tag removed.
Parts are still easy to get and you won't be able to find a JD or Kubota equal in size to match the price you can get a 6284 for.
11K might be a bit steep pricewise, I just searched around on CL and found one with a loader and 54" deck (not as good as the 60") with 133 hours and turf tires for under 8K. Another one with 10 hours & 60" deck no loader for 7500. So there's still some deals to be had!
As far as comparison, I'm not up on JD model sizes.
I was a bit skeptical about the on-demand 4wd, but I put a 5' heavy duty bush hog on the back of the 6284 and it would walk backwards up a VERY steep hill, while mulching, never slipped a tire. I was getting uncomfortable the incline was so steep!
It handled the 5' so easy I just purchased a 6' and next month will be bush hogging my 7 acre field. The loader is strong, I like the CAT engine. One downside is the motor doesn't like cold weather, so heat it up first if you're going to be using it in the winter.
Good luck!