My family and I (12 people) went tubing on a sunday afternoon. It was easy to book and easy to find.
The shuttle was quick and the driver was fun. The entrance to the Rum River is a nice slope, so easier to get into the tube. It took about 2 hours and 45 min.
There is a huge drought right now, so it was a little low in a few places, but we were all able to stay in our tubes for most of it. There were also quite a few trees popping out of the water that we had to avoid. It was nice to be able to touch the bottom for most of it.
The only downside was walking up steps and a hill to get back to the cars.
There is a small store and restrooms at the shuttle site.
I will definitely go back!