Not saying the Master 6 is not good - I love my Master 7. While it's not musical. It's true. Just like the GS-X is true. If your looking for musical the GS-X will not give you that. So if you say musical is better than yes the Master 6 is better in that way..
When I hear the term musical - I think of color or something is being add that's not in the track it self ie. Making it musical.. That's just me..