Before I made the jump to VPS/Dedicated I used host gator for my shared hosting needs. They were the best shared host I ever used and I would recommend them to anyone.
Going over cpu usage is different then bandwidth. You can go over your bandwidth and still be good. What they don't like is when you have 100 visitors on your site...that slows down the server and makes other sites load up slower that are on that same shared server.
In the hosting world, you get what you pay for in most cases. If a hosting "plan" is advertised, you should not be punished for using it!