Icy Dock was my first purchase - was very excited to buy it.
It wasn't too long though until I realized that monkeys designed the backplane... "slow" monkeys at that.
I've had two separate problems with my machine not functioning properly because of the damn cable connections there. (One when the machine had been running for weeks, with all drives spun down)
To me the Supermicro is a better design - although to be fair, it is not yet fully populated and I may end up swearing at this one in a year, and swearing by the Norco.
An overall indication of quality to me can also be seen in the trays. Once I got my Supermicro, I realized what a good tray is.
I'm no SM fanboy - but I do hate the Icy Dock. I'm amazed some people like them - especially when they are more costly and have some (serious to me) design issues.
Oh and my Icy Dock fan SUCKED. I did remove it and am relying on good airflow from my Antec 1200 for now. I could hear that damn fan, easily, on the other side of a door, which was located ~10 feet away from the server, and about 5 feet away fro where I was standing.