There is a KOA in Cartersville but............it's changed hands and the new owners aren't too concerned with upkeep. Managers are trying hard but hands are tied.
I have driven through Harvest Moon RV Park at Exit 306 on I75. It looked like a nice park and even stopped in and talked the person on duty. The offer free WiFi and have a pool.
Can't say anything about the KOA mentioned above. Never been through it. My personal preference is to stay away from KOAs
My personal suggestion from experience is to avoid the Cartersville KOA. Too many rules, did not honor reservations or requests, speed bumps, do not answer the phone for many hours during the day, did I say high speed bumps. On one occasion, I had requested a site to be able to receive satellite, and they refused to honor that request. On another occasion, I had reservations far in advance of our travel dates. A week prior to our reservations they called and said we did not have reservations as they had just booked a caravan and they would take all the sites to include the one I had reserved. They said I should check with some other parks in the area for openings.
One KOA even had the sewer connections on an uphill so the sewage would not even empty from the RV. Had to pick up the sewer hose and walk it to the the dump. When I asked why he said "that is the way they designed it".
I had avoided KOA's in the past for such policies. I will avoid in the future.