I love staying at Stone Mountain. We were just there a couple of months ago. Most of the sites are relative level, however, there are some that are extreme. I had a pull through a few years ago that I came the wrong way on the road because it was so un-level, that I couldn't get the back up high enough or the front low enough to get even close to level. Being in the site backwards I was able to jack the front up about 5 feet to get it level. The back of a 30 ft trailer was almost on the ground at that point.
I didn't think the sites were too crowded. They don't give you 100 ft of space for each site, but there was enough room. I've been in some where your slide just about touched the slide of your neighbor.
I always enjoy staying there.We used to go to Atlanta twice a year for a Taekwondo tournament, and have stayed at Stone Mountain, Allatoona Landing, and Atlanta-Marietta RV Resort. I like Stone Mountain the best, but it was the farthest from the tournament. I also have to attend the laser show and hike the mountain, while I'm there. Sometimes we take in some of the other activities.