Rock & The DA * 50-135mm

I needed a fast tele-zoom lens for concert work and found that the Pentax DA * 50-135mm really seems to suit my needs.
I suppose you could say it is the equivialant of the the 70-200 L f/2.8 I used with my Canon 5D II.
Click here to see a full size crop of the detail. I was about 40 feet away from this guy and he was moving all over the stage..