Progasm 20th anniversary

I want to buy a progasm. The newer, 20th anniversary edition is out but it isn’t available anywhere other than the aneros website, which I can’t order from (also Amazon isn’t really available here, but I couldn’t find it there anyway).
I’d like to know if it’s worth waiting for it to be available elsewhere, or just buying the older version. How much different is the new progasm to the old one? Is it a lot better/worse?