Very mixed feelings about our Eclipse corner 5. We thought we were crazy when we noticed that it was holding heat without a heater or a light on (the temp has never dipped below 80 without excessive water change). And let me tell you: it is no fun to watch a control freak realize they can't control something, especially when the lives of our fish hang in the balance.
The filter impeller is a bit testy: it sometimes needs to be monkeyed with and jiggled to get it to start pumping.
Placement of the light at the very front is a bit of a mixed bag. For one, it gives the fish a place to hide and allows space for a low-light plant. But at the same time, it would be nice to have an evenly lit tank. It's especially annoying to have a one-piece hood where the light is attached, and every time you go to feed the fish or do any internal maintenance, you have to point your desklamp at the tank to see what you're doing.
On a last note of whining, the power cords for the light and filter are fed through tiny semicircular holes on the back of the hood, and constantly wiggle themselves free and cause a problem every time you try to close the hood.
All in all, it's a good value for what it is. we chose this option over putting a setup together piece by piece, and saved a decent amount of money. But, if given the choice again, I would just go ahead and put a system together from scratch. It's worth the few extra bucks.