Saw a WD 2TB external yesterday for $220. I forget where, i will have to look around.
WD is not very clear on ther web or in packaging what the different levels - Essential, etc. include. Mostly software variation as far as I can see?
Bought my wife a WD extrernal for backup on her eMac. Simple setup works well for what she needs.
I just buy internal drives and shove them in a DiamondMax external adapter with eSata. It is $50 at Best Buy, on sale at $35, but $20 after rebates recently.