Question to some of the storage pros Options

[Harkonnen]

I've decided to get this 4-bay drive enclosure or the cheaper non-raid variant.

The most cost-effective thing I can think of is to fill it with four 1.5TB WD Green power drives, running independently for a total of 6TB (5.5TB NTFS).

Or run it in RAID5 and fill it with four 1TB enterprise/raid-edition drives for extra speed and data protection. However, I've heard RAID5 isn't fool proof on rebuilds and having nearly 50% of the space seems like a huge tradeoff. (I'd need to get 1TB drives as I've heard the WD green drives don't work in RAID and I'm never buying Seagate again).

Thoughts? Any opinions would be great.

I don't really need speed so much as space and protection.

[Harkonnen]

Yes I'm familiar with TLER on WD drives.
I won't be setting up in a raid because I just remembered partitions over 2TB need to be formatted with GPT partition style instead of the MBR that NTFS normally uses... so it won't be recognise by any OS that isn't Vista, pretty much.

Which is bad because I was going to mod/marry it to a Western Digital HD Media Player.

I tried talking to WD and asking if they were going to release a firmware update for the Media Player to read GPT-formatted drives (considering that 2TB+ Western Digital drives are on the horizon, it would be ridiculous if their own media player couldn't read them) but all I got back was a standard THIS ARE COMPATABILITY HARD DRIVE LISTS SIR.

Hopefully it will be able to read the four drives seperately with the enclosure acting as a 'usb hub', but tech support refused to answer my question on that as well. Crossing fingers it will work out.