My book Studio edition II, Esata and raid 1 and checking raid manager

I posted this question already but it was in a solved topic so i thought id better get my own topic.

I have a Studio edtition II and i want to use E sata, ok so you set it up using fire wire or usb and then use E sata. This sounds simple enough. But how can i check if a drive has failed if i cant use the raid manager with E sata ?

This would mean switching the drive to Fire wire once in a while to check. I would find this most inconvinient and i hope the people at WD have thought this one through and found a solution for this. I chose raid 1 because i wanted the extra safety but if i dont know if a drive has failed its still not safe.