Here is our compatibility info thread.
And while it may not be "cheap", this is the one that I bought and it works great: Amazon.com: Seagate FreeAgent GoFlex Desk 1.5 TB USB 2.0 External Hard Drive STAC1500100: Electronics
I use the western digital my book and have had no issue
Another thing you could try is using a newer beta version of d2x cIOS. Guide below in my sig.