I'm looking at DAS solution which will likely be a 4 disk RAID 5 array. Probably going to buy from OWC as I also have to order memory from them for new iMac and another USB stick. I would also like to have another backup cloned drive of the data stored on the RAID 5 system. Will I benefit from having the TB2 DAS solution or would I gain nothing without using SSD drives (which I don't plan on doing)? I would be using standard 3.5" drives (not sure which ones yet 5400 vs 7200 and brand). This will mainly be for storage of RAW files for photography and a backup of movies and iTunes etc... OWC has there ThunderBay 4 RAID with TB2 or they have their Mercury Elite Pro QX2 which has USB3, FW800 and eSATA. Both are 4 bay systems but just with different connections. Obviously the USB3 system is a bit cheaper and I think comes with 7200 drives where I'm not even sure what drives come in the ThunderBay one. I could also buy my own drives. I guess the other issue is TB2 would allow me to daisy chain another backup clone drive onto the RAID system without using another port on my iMac. Any and all advice is very welcomed. Thanks.