I might get an Ultrium 2 or 3 drive (currently 2 for $120 or 3 for ~$175 on ebay) and use the cartridges. 2's do 200/400Gb and 3s do 400/800Gb and its VERY stable.
1Tb = 2 x Ultrium 3 at ~$25 each = $50
1Tb = 40 x BD-RE at $8 = $320
drive here: Quantum Ultrium LTO 3 internal tape storage drive, LTO-3 | eBay
people do like the LG WH12LS39 if you go the Blue ray route
As an aside Quantum stuff (like Ultrium) is reportedly unusable on Macs, but has a good chunk of the PC business market