Eek - now I'm glad I wait a few months before buying each disk for my NAS.
Not doing it for this reason but rather financial ones :) But as I have a totally mixed bunch of sizes I have no RAID and a disk loss would be horrible.
>>GekkeP+(OP)
Have to be careful doing that too or you'll end up with subtly different revisions of the same model. This may or may not cause problems depending on the drives/controller/workload but can result in you chasing down weird performance gremlins or thinking you have a drive that's going bad.