Best eSATA JBOD?

redlandmover writes "I already have an HP Media Server (upgraded processor, and memory) that has already been upgraded internally to 3.5TB. I'm sure everyone already has their favorite backup solution (RAID, WHS, a billion external hard drives, etc). My question is: what is the best JBOD (Just a Bunch of Drives), eSATA-connected, external hard drive enclosure? (Preferably, at least 4 drives.)"