I have been offered a used receptor pro, and I think I am going to buy it, whether or not Garritan's Steinway will run on it or not.
I will buy Akoustik piano, because I need a good upright such as the Steingraeber.
From the demos that I have heard, I am not convinced with Akoustik piano's Steinway. Apart from Garritan's, I like Galaxy's most. I also like Galaxy's Baby Grand, so I think about buying Galaxy, too.
I know that Galaxy II is not (yet) officially compatible with muse's receptor, but I was told that Galaxy I is, and I suppose, Galaxy I Steinway sounds very similar to Galaxy II Steinway (btw. are there samples of the old Steinway available?)
However, to me it seems stupid to buy as well Galaxy I (for immediate use on the receptor) and Galaxy II (to play with on my laptop now, and for future use on the receptor once it - hopefully - will be compatible)