I have an old 8000 lb Warn which has been pulling my overweight 4by and trailer out of trouble for the last few years. When I bought my JK this year I had no hesitation in pulling it off my old vehicle and fitting it to this new one. I'm sure it will do the job for me no worries, however I will use a snatch block for the tougher pulls.
As a few have said, if you can afford one of the higher rated winches, then go with it, but if money is an issue then don't worry too much, an 8 or 9K winch will do the job.
Better to have it and not want it, than want it and not have it.