I USED to play a TON. I own every PS2 DDR title ever released in the US and I've played a few that weren't. Started with DDR 3rd Mix in the arcade, have played 3rd, 4th, 5th, MAX2, Extreme, SuperNOVA, and SuperNOVA 2 in the arcades, as well as ITG and ITG2, plus four different versions of Pump It Up, plus ParaParaParadise, and that's only counting DANCING games and not other rhythm games. XD In high school and college I'd regularly put in several hours a week.
I need to get back in the habit and burn off this 60 extra pounds I've put on. >.>;
But as I said, I'm not world-class. I've only won local tournaments; I'm not actually all that great at Perfect Attack and usually don't worry about my score as long as I pass.
And as for Sandstorm, I don't remember the specific steps but I do remember my opinions of the stepcharts.
Edit: Using the keyboard (not on foot!) I've gotten a B on
http://www.youtube.com/watch?v=Ry8joiMZkrQ.
Edit 2: No, that's not the same stepchart I played... Same song, but the steps don't quite match.