We recently had a drive go bad. I had a long talk with the guys from G-Raid.. It was interesting to learn the dynamics of how the drives work and are put together.
We sent them in 2 and got 4 back and did not stripe then. I have them daisy chained but not striped or raided. Thus if there is a future problem We can send one drive and not 2-4 at one time back for repair.
I also found out it depends on the cards that the drives have in them as to how its best to use them. If you have questions call the manufacture.
Cheers,
John