@Curtis
The 3000D mouse has a few things going for it:
It is a great mouse ergonomically to use, for my use it is the best mouse to use for comfort that I have ever used, the 3000D also had a great keyboard to boot. Have no idea why more manufactures didn't take the design.
Secondly, it was made at the high point of the companies history and that holds a higher value. In today's world the 3000D is sold for more than a 4000D (with a similar processor) on many if not most occasions, especially if the 3000D didn't have motherboard damage and has later chip versions.
Hope you don't miss it too much:).