nothing beats gcc, anyone who thinks they can argue, I will point you to the nearest man pages.
If money is no object, then the high end vector compilers from Cray, SGI, etc kick the crap out of gcc. And what man pages are you talking about? Do you think the man pages originated with the GNU project? Every unix clone has them. And its not like they can tell you a whole lot about the merits of a particular compiler.