Vergelegen in my mind must be one of the true gems of the Berg. Long ridges that seem to stretch on forever, very do-able passes, well sheltered caves near the tops of most passes, some truly magnificent views from the top, easy 2 day ascent of Thabana Ntlenyana, with a 3rd day back down again. Did I mention the truly magnificent scenery? There are also a fair number of Khulu's in the area (
see this page for details).
It must also be one of the least visited areas of the Berg, so if you are into getting away from the crowd, this is the place to go. Facilities at the bottom are commensurate with the traffic it gets (ie, don't expect more than a working shower and a flushing toilet...), but well worth the visit. Although the 5 days I spent up there were cold and windy (I guess thats what you expect being up there in Aug), it has left an indelible imprint in my mind, and a desire to go back and explore further.
Another interesting spot on the lower reaches is the sulphur spring which attracts the Eland in their droves. We saw a herd of about 40 Eland hanging around there on our trip.
Have fun.