I went with a Warn VR 12k, which I paid about $700 for. It came with steel cable and I have no plans to change it. The advantages I've heard are synthetic line is much lighter, but as CarringB said it can get cut. Steel cable is heavier but pretty bulletproof. I used mine for the first time yesterday to help a friend pull down a pretty good sized pine tree played over on another, and to pull a huge maple stump (several thousand pounds) to a more accessible location to be hauled off. I was very impressed with the 12k. I was sitting on wet grass and it actually started to pull my van a couple times when the stump got hung. This was with the van in park and E-brake set of course.
Unless you really want to shell out for the synthetic rope for the bling factor or really need to lose the weight I don't see the need, especially if you very rarely need a winch.