These always go on sale around the holidays. This year the EZXs are $49. I bought a few back in the day when they were on sale for $29. I think I read that Superior Drums is going to a 3rd version now?
Yes, they do, but not the converse with EZD2.
The only thing I'd really like to add to my EZD sounds are more brushes and mallets. I don't think the price will ever go back down - regular price now is $79 for the EZXs.