Indeed the upgrade from Editor 2 to Studio 4 is $149, which I think is a fantastic price. Given the new features, I think it should be well worth it. Funny, like some others, I didn't initially see the upgrade path, but after checking with Celemony via email (they got back to me so quick it was unbelievable) it was on their page if you log in and then click to buy the full thing--but you have to scroll to the page bottom, and there are several upgrade paths, including Editor 2 to Studio 4--
I think I'll go for it, once I check with my secret accountant....