I doubt it because you can store so much memory on hard drives or cards now. One good thing about the Yamaha MD8 is that it has a very nice mixer and I'll hang onto it just for that. I'm sure it wouldn't be worth much as a resale, anyway.
You can do alot of things without a keyboard these days. Alot of people aren't really even tampering with them. There is way too many softwares that take the place of that.