I was a member on both rivals and scout for several years, mostly to follow recruiting and get inside info.
The inside info aspect across the board has pretty much dried up due to the sites being seen as legit media now a days. Admins can't really post what they are hearing like they could several years ago. There are a few posters at each place that provide info, but not a lot.
So that leaves recruiting, and think rivals has better iowa coverage and national coverage. I like Rob and think he does a good job, but I didn't find myself visiting the scout site much over the past year, so I cancelled my annual subscription in October.
I'm curious to see how the 24/7 site does, they seem to have a focus on recruiting, which I think is key if they are going to make it.