Although I didn't end up buying one I was recommended this one in the D750 thread a few weeks back by @Livin The Dream.
http://www.maplin.co.uk/p/icy-dock-...&ranSiteID=TnL5HPStwNw-b797jMWE0iOuXohoQKJyjQ
That looks like just the ticket, thanks!
That's the one I have Tim. My concern was whether USB3 was going to be snappy enough, - you can't tell the difference! The price difference for a thunderbolt version wasn't good value IMO. I have just my operating system on the internal HD, with two 3TB drives in RAID0 (mirrored) works a treat.
Icy box do one too.
Raid0 is not a mirror.
Remember kids, raid is not a backup. Even in mirror mode make sure you still have separate copy of your data in case of hardware failure/deletion/corruption/fire/theft/flood