then a RAID rebuild could be a sensible thing to do before forgetting the affair and moving on?
In all honesty, yes that's probably the best course of action in your circumstances.
What you could do is leave the RAID as RAID1, but just reformat it (or even better do a quick one pass zero overwrite) ....you might as well keep the benefit of RAID1.
Then, you might want to consider making use of TrueCrypt (or other tool of your choice) to create encrypted disks (not "whole disk" encryption, just little disk images of manageable sizes - or larger sizes if you know you're never going to be doing remote access)..... so then at least your data is encrypted at rest and "they" can copy it as much as they want but would be able to see
all.
