potential purchase

1. Go with a 7200rpm disk for this.
2. Go with a slower rpm disk for this. Performance will be slower than with 7200rpm disks but still pretty quick.
3. For cheapest price you'd go with a low capacity consumer disk
4. Longer warranty disks tend to be more reliable but they're also more expensive.

You have needs that in some ways conflict with each other. What capacity drive are you after? You do have to decide how important different things are you to and make a decision based on that.

I've heard good things about Hitachi on the forum and may well get some of them when I next purchase disks (I haven't decided yet).

Thanks,

I'll probably only need 2 x 2TB disks as we don't have masses of data to store, so i'm looking for a disk that has reasonable transfer rates whilst not being too noisy and not too expensive, if that makes any sense!?!

Regarding noise, see http://www.readynas.com/forum/viewtopic.php?p=285662#p285662

So getting a Samsung could be a good option if very noise conscious. I would say the slower RPM drives should have good enough transfer rates for you and would be a good option. Personally I'm not a fan of WD but some other's like them a lot.

The NAS also has fans, so it will make some noise independent of the drives. Take that into account when you decide where to put it (your entertainment center might not be the best place!).