I have one, but I replaced it with a Dolphin. It had NO problem in my deep end-- 5.5 feet. The 65 won't do deep ends, but the 165 will.

When it works, it works quite well. When it works...Polaris sent me a whole new set of guts.

The way it works is this:

At the bottom a jet of water acts as propulsion and a broom that "sweeps" debris into a catch-bag. This is such a simple mechanism that running down to 8' should be no problem. The piece on top drags the hose for the bottom jet around the pool in a random pattern. That's where problems occur. There are 4 or six jets that are used as thrusters in various combinations. This is all mechanical since it's not electric. This mechansim, when it functions correctly, is very effective. When it gets at all jammed or clogged has immediate disasterous effects on the performance--the unit will coil up the hose and get jammed in that position.

If there was a good way to clean it--like pouring vinegar thru, it would be livable, but there isn't. When this happens, Polaris should send you a new mechanism--they sent me one--but not when it's out of warranty.

So I guess I think it's too fragile a design and cannot be counted on to reliably clean your pool everytime, for years on end.