For those that have ESPN Insider, here's an analysis of the top 6 or so FA starting pitchers left on the board:
Sanchez pretty clearly the best available
The gist is that Sanchez has had at least 3.8 WAR the last three seasons, his velocity is up a tick since his injuries, and his periperals are better. The other SP's they looked at were Jackson, Dempster, McCarthy, Marcum, Liriano, Villanueva and Lohse.