I've been to JRSP several times now and each visit gets better.  Camping on the River edge is very peaceful and convenient if you just want to drop your own tube in and float.  This site isn't very wooded and therefore not much visual privacy but there is lots of space to spread out.  The sites are generously sized and flat.  A few negatives:

1. There is a bit of a walk from your vehicle but it's not bad.

2. The bathroom is just a potty with hand sanitizer, no running water.  

I also stayed in a 2 bdr cabin on a return trip which was very nice.  I was impressed with the accommodations and the A/C which was enjoyed on our hot August nights.  The best part of both trips was the River.  Absolutely clean, crystal clear water and never crowded.  Both of my trips were during the summer and over a weekend and we seldom came across others.  It was if we had the whole park to ourselves.  I'm going back again this summer.  My boys are excited to rent the kayaks again.  This is a great experience for couples and families.