Thank you everyone for your indepth replies, this was exactly what I was hoping for - you're the best!
It's interesting about the pros and cons. I hadn't considered just how much the filter would take up in the tank. Is it any better in the 5 gallon?
The light is also a biggie for me - good to know that it has incandescent and that it can be replaced with something better.
I guess I was hoping this would be the wonder tank. Convenient size, no HOB filters, feeding door, etc.
Perhaps I'll stick with the Eclipse Hex, then - there's less to modify and they're about the same price. I just wish they still made the series in smaller sizes like the 3 gallon.
Thanks again, everyone! I really appreciate your help ^_^