One of the most appealing features of this deal is that the player is guaranteed to be Rockbox-compatible (at least based on the description).
There are two versions of the E200 series: v1 (which is Rockbox-compatible) and v2 (which is not). If you buy a new one, you are pretty much guaranteed to get a v2. If you buy a refurbished one from other places, it is a cr*pshot.
If I understand correctly, you should be able to use an up to 8GB microSDHC card with Rockbox for a total of 14GB capacity. Of course, 4GB cards are priced more reasonably (in the $20 range). So, you are getting a 10GB player with great features for $65.
If you are concerned about it cr*pping out (I have seen many complaints in buy.com reviews), make sure you use a credit card that provides extra warranty protection.