Have been running biopace for over a year. See link to FGG in my sig. Works great. OP: When you tighten the chain, get it very snug with the cranks vertical. They'll be just right when the cranks are horizontal.

I have NO problems with it. Ive run round and biopace (depending on what I have when I build the bike) and I can't tell the difference. I have 3 biopace cranksets (one in use) and my next bike will use them to. I just have no reason NOT to.