I heard there was a new one in the area, not sure but Hilton Head Island Motorcoach Resort is a good one. Do your research in site selection by looking at Google maps and not being near the noisy activities outside the fence, some construction or something near where I was. Can't remember the site number I had, just research carefully. It was at the end of the lake in a corner, non lake view where I was. Didn't care for it.
Also consider if you want to be on the island or off the island and more around town stuff.