When it comes to selecting books, I try to cover three categories:
1. Reduced juice/free half points
2. Big selection of offerings
3. Recreational customer base for dog-friendly lines.
Of the books I use, they break down by category as follows:
1. Pinnacle, IIS, Hollywood, Canbet, Skybook
2. Olympic, 5Dimes
3. WSEX, Intertops, Carib
Pinnacle would easily be my top choice overall. There would be a number of contenders for 2nd and 3rd. So, if I had to choose only 3 books, I might choose to go with what I consider the top book from each of my categories: Pinnacle/Olympic/WSEX.
While this likely wouldn't be the ordering of my top 3 books overall (especially since I place a big emphasis on reduced juice), it would nonetheless give me a good balance.