Most, but not all, sites have lake views.  During the time of our visit, only one area was open for camping (sites 25-58).  We picked site 42 out of a handful of available sites, all seemingly equal.

Apon arrival we discovered sites 42 and 43 are very cozy with each other.   A family with a large number of small children was tent camping in site 43, basically using site 42 as a spillover (literally, the site 43 water is physically located inside the edge of site 42, and as children were getting water, this created a small muddy run towards our trailer position).    Suffice it to say we were pretty displeased with the proximity of the neighboring camp site.   See picture.   On the positive side, these 2 sites would be a great setup for a multi-family or group camping event.

We walked the next branch of the campsite which was not open, and found that sites 3-24 are much more to our liking with regards to elbow room and privacy.  Our next trip to this park will be on that branch.

I would recommend this park with the caveat of doing site research ahead of time.

Camp map is here:

https://www.sas.usace.army.mil/Portals/61/docs/lakes/hartwell/PlanaVisit/TwinLakes/FY13TwinLakes.pdf