Who has Powercranks?
Good question.
There was one guy who was a great climber and wanted to do well in stage races but couldnt TT. He worked with powercranks and his TT improved dramatically. Like 2-3 minutes better over 50 km ITT. Thats like 50 watts better at least sustained over an hour. My money is he'll win the Tour someday.
Another guy was a flatlander, more suited to the Classics like Paris Roubaix, which I think he will still win one day. He started using powercranks, and low and behold became a really good climber due to improved power and efficiency. WOn the queen stage of the TdF this Year.
Yes, two words: Basso and Hincapie.
You would be hard pressed to find two riders already at the top of elite cycling who have then gone on to make such dramatic improvements. The only reason they dont come out and endorse them is that then everyone else would use them too. IMHO
Need I say more.