Don't ask ME about Dolphin right now--Mine is 2 years old and this season started giving me nothing but trouble. I would look at AquaBot or Blue Diamond instead.

I also have a Polaris 165 return side. It works OK, (the Dolphin when working is better), but Polaris is fragile too. Luckily, the company was really up on honoring their warranty, so it works great now.