I need to buy some new hard drives. Currently I have WD-RE2 500gig. Also have some WD-RE2GP 1TB. Would like to go with some more of the WD-RE2GP 1TB but I can't find them from a decent seller. So now I'm debating between the WD RE3-1TB and WB Black 1TB. Price difference is about 60$ per drive. Any thoughts? Thanks!