Hi YAE4Volcom -
We have 2 eclipse tanks currently. We have a 47 Gal, and 6 Gal. I really love them. They're very nice looking, and we haven't had a problem yet. In the big one, we've changed from the standard lighting to VHO (for now anyway), and it bolts right in. When we wan't to upgrade again, we're gonna have to buy the whole package for compact florescent. (not too expensive though).
The 6 Gal hasn't had many upgrades - it's FOWLR. I'm looking into a 3 Gal eclipse for dwarf seahorses. I can get it for about $30.00.
I know they have a 29 Gal, but not too sure what else. As far as I know, they only have Tall Tanks, I've never seen Long ones. Don't have pics yet, hopefully soon. Lost the cord to go from the camera to the computer...
HTH