I have noticed that my 3ware controllers, after updating firmware recently, have removed the JBOD option entirely, classifying it as something you wouldn't want to do with that kind of hardware anyway. I believed then, and even more so now, they are correct.

Use the RAID-0 disk trick to be able to utilize the controller cache. And regarding write-back vs write-through; I believe write-through is equvivalent to disabling controller write cache, however it WILL cache the writes in order to respond to future reads of the data being written. I would guess, but I don't know, that this also goes for disk-level caches too, though, so it probably doesn't matter.