If you're using a newer MacBook Pro I've seen some people swap out the disk drive bay for a 2nd SSD. This doesn't sound like much but that allows them to run a RAID 1 setup on their laptop (1 drive with a mirrored second drive).
I import from cameras to a couple NEXTODIs on the road, then from the NEXTODI to the SSD. I don't delete from the NEXTODIs until images are all the way through to offsite backup. The SSD is not RAID, and worse, the Velociraptor runs in RAID0 for raw (pardon the pun) throughput, but I always have at least two copies on diverse systems.
These guys talk about doing that with a RAID 0 setup: http://www.youtube.com/watch?v=cKaXZVHcdGM