Mumzie-
I got a Mercury punched up today. I didn't get to throw it too much, but I've got an idea now. I never had a Sonic X, so I cannot compare the 2. What I can tell you is that the Mercury has very good length, and a hard backend. It wasn't a snappy reaction. I was suprised by the amount of hook it had on the backend. These of course are initial observations after just 1 game with it. The hit and roll reminds me of a ball that should cost twice as much...the hit is outstanding. I had it drilled 5.5x4, no weight hole.
Don