For some reason, I had just assumed as everyone else seems to have that Helton was a washed up cornerman with a great batting eye, but no power to take advantage of Coors Field's thin air. But looking at his 2007 numbers - .320/.434/.494 - he was still a productive hitter, who could significantly help you in batting average. And while 17 home runs isn't ideal, in a deep mixed league, it's useful enough.
A back injury ruined his 2008, and you wonder whether it had a hand in his decline in previous seasons as well. (He had back spasms in 2007 and some back issues in 2005, too.). In any event, he's healthy now and has hit a couple home runs in the last five games this spring.
There's no guarantee he'll bounce back even to 2007 levels, but you can get him fairly late, and given his history, his ability to hit for average and his home park, he's got more upside than the Casey Kotchmans and Adam LaRoches of the world. I'd have no problem with him as my corner in a 14-team mixed league.