From my totally initial impressions that I don't trust enough to vote with, and also just going Pro to Pro...

Tron. I only really got to play half a ball on one, but the shots seemed to lead to only more speed, and the variety was really cool.

ACDC Pro I got two games on. I liked it, but there are a few rules things that bugged me, and the machine that I played on more than half the time gave unsavable SDTM drains from exiting the pops, even with that little spring thing there. It has a lot of speed too, and if I was on a machine that wasn't doing that, I think it would totally rock.

I haven't played either as an LE, but that bell looks amazingly fun to hit. The ramps look cool on Tron, but I like my toys to be interactive whenever possible. I know they change colors to correlate to modes or something, but I like the ball to actually smack things in the games