First, let me confess that I have primarily been an Imperial Player and I have gotten pretty good, if I do so myself, with Star Destroyers. But last night I was helping my friend learn the game so I took a couple of MC30s (we were only playing 200 points for his first game). I have fought MC30s more times than I would like to count and they seemed to be really great ships. I like the red black combo of their dice and they are fast.
So MC30s may be fast and hit hard, but they don't turn very well, especially at speed 4. I know it was my first time with this ship, but I was really surprised how hard they are to fly.