I had a SSB (Shallow Sand Bed) and didn't like the accumulation of stuff. In this tank I can turn up the flow and feed that crap to the skimmer. I am building a sump for my skimmer and fuge (cheatomorpha). I think it looks neater and easier to siphon detrius and not have to replace any substrate. This tank was started Jan 04.
Looks great but I'd be reaaalllyy careful stacking LR on a piece of tempered glass. Even a small amount of pressure on a sharp piece of rock could be enough to shatter the bottom-glass.