During the time I had the 5604, I tried several other cases and the 5604 won me back each time. But recently I tried a case that was good enough for me to think I could switch permanently, so my 5604 is on its way back across the country to its new owner. The new one is nowhere near the price range of the 5600s, and it really isn't all that much better for my needs from a case, but I just have to change things periodically... ATers seem to know how that is.

Just for some trivia, the Tt SViking (discontinued in the US market I think) was based on the same chassis as the 5600s. You can find it in others too, like the XClio Windtunnel and the Tagan Obelisk (really the same case) - but the quality of the drive slides on those is not as good as the ones with the 5600s, being all plastic and no rubber bushings for the HDDs.
Luckily, if my mind changes again, the 5600 series is always there and I can get yet another new look w/o any loss of the functionality of my 5604. I wrote the review of the 5604 on techIMO, so you know my thoughts on it (I'm zepper there too) as I don't pull any punches. I believe that one really can't get any better functionality in a midTower case for under $100. and it would be hard to do better even at over $100. About the only convenience I would have liked is a more easily removable front filter. But I put a real filter on my front fans anyway and the bezel comes off the 5600s quite easily for cleaning/replacing the filter element. My new case does make filter maintenance easier as when you open the front door, "Whoop, there it is!".
The Coolermaster Centurions and the Enermax Chakras are also very nice but they only get a 3/5 on my Casitude (tm) score. No rubber vibe bushing on the HDDs and all that mesh on the front lets you hear any noises from the inside. There are tons of cases of different brands based on that same chassis so maybe one could be found with a door over the mesh.
And the Rosewill R6A series is very good too as they are based on the same chassis as the Antec SLK3000-B, the Tt Tsunami, etc. The only real problems with those are that there may not be room for long cards (generally a bit more cramped inside than the 5600s), and there is little room behind their doors. I use a Sunbeam Rheobus fan controller on occasion and the knobs won't fit behind those doors w/o recessing the Rheobus a bit. I like the looks of the R6AS5-BK version very much. Those may even be slightly better coolers than the 5600 series as the HDDs are in the "proper" orientation for less air blockage. Though I never had any cooling problem with my 5604 - just an observation... Here's a review:
http://www.thinkcomputers.org/...x.php?x=reviews&id=663 . Unfortunately, the fanboy author of the review seems to have little depth of perspective in the case market, but he does catch the high points.
.bh.