New to the BCM system (we just picked one up). After looking at the insides, the HDD looked like a standard 20Gig HDD. I know that they offered a mirroring option, but is it necessary to purchase a kit from Nortel? Figured that since it's based on NT 4.0, there may be some way of dropping in an off the shelf hard drive (same brand/size) and mirroring it somehow.