Here is how I use Miroslav Phil:
1) There is a subset included in Sampletank 3. They have been updated and processed to fit within ST3 and its effects, and all sound excellent. This is what I mostly use. It's most definitely a small subset.
2) I imported all the instruments from Miroslav into Sampletank. This means I have the instruments/samples but only the custom programming to the extent that ST3 supports it. For instance, some of the imported instruments use expression (CC11) and they do not work consistently as intended inside Sampletank. I've concluded that the original MP is too problematic to use in general, and have chosen my few favorites MP instruments and defined custom instruments for them in ST3.
I really like how the ST3 MP instruments are playable with "expression" using velocity, as that's sort of how I play. Using CC1 and CC11, as is necessary in e.g. Hollywood Orchestra and Albion, is less intuitive to me (but obviously opens up other possibilities).
I really like the tone of the original MP, and it was first symphonic collection I "connected" with, so I'm probably going to get it for no other reason than I like MP 1. (At least they don't call it MP 1 and MP One -

).