Harmy, just throwing my 2cents in here. I'm an video editor by trade and we exclusively use Western Digital Green drives at work. I edit off of them daily and they've never let me down. We have 50 or so of them in regular use at the office.
http://www.newegg.com/Product/Product.aspx?Item=N82E16822236404
Don't get me wrong, WD Caviar black drives are fantastic, high performance drives, I have a couple of those too, but for work we edit and archive with the green drives and they perform fantastically. We use the 2TB models (link above) and have found them to be very reliable and reasonably fast. There's also a 3TB version on sale for $114.
http://www.newegg.com/Product/Product.aspx?Item=N82E16822136874
I agree about staying away from the Red NAS drives. The Green's are a great low cost, reliable alternative.