I have two OWC drives that can be connected via FireWire 800 or eSata (or USB 2.0, which doesn't count anymore), but our Late 2012 iMac uses Thunderbolt. The first thing I did was connect the iMac to the drives via an Apple-supplied Thunderbolt-to-FireWire adaptor, which worked fine in terms of I/O, but there was some kind of incompatibility in that whenever the iMac would go to sleep, the drives would not go to sleep but would be disconnected without first being ejected.
I bought two flexible eSata cables to connect a LaCie 2-port Thunderbolt-to-eSATA hub (the hub appears to no longer be sold by OWC) to the two OWC drives. The cables and the whole kit work fine and solved the disconnect problem. In addition, the flexibility of the cables was very helpful in our limited space. I was used to dealing with the typical stiff eSata cable, and for me the flexibility was worth the extra cost.