The Compaq/HP controllers I worked with would run data integrity checks on any RAID set when the controller was idle. All it did was read the entire RAID set, and check for errors coming back from disks indicating one might be failing.

Definitely ensure some sort of full read is done to the array at some point, even if under linux it is a simple cat /dev/device > /dev/null. I had a 2 drive failure on my RAID 5 software array when one disk died completely, and a second one had a bad spot. I did manage to recover the majority of data in the end, but would have preferred to know ahead of time one of the disks was having problems.