Which Western Digital Caviar HDD is more reliable for a long time back up storage?

I'm planning to buy a new HDD for back up storage - music, images and program installers; I'll be using my 1tb 7200rpm 64mb Western Digital Caviar Blue mainly for installed games. Which Western Digital Caviar HDD variant will last longer for back up storage?

Black

Blue

Green

Red 

Reds are designed for Network Attached Storage, and Blacks are "premium" grade.

So, id go for Red for long term storage.  

Thanks for the reply!