I would go a winch with rope rather than wire, the more weight you can keep off the front of an already front heavy car the better.
As far as power goes, I have a 9500 lbs winch and have never needed a double line pull so far.
My experience:
Depending what your sort of driving you do, for the money your halfway to a Chinese air locker, which would be much more useful if your not locked already.
Also if you need to get a bar to mount the winch to as well, thats more money toward traction rather than weighing you down
