Had to go with the Pistols. There are very few bands that can have the impact and influence that the Pistols had, with only Nirvana and the Beatles jumping to mind in terms of their impact on popular music and culture.
But let me also say that rock fans don't give Rod Stewart even close to amount of respect he deserves. Forget "If You Think I'm Sexy", and listen to Stewart's original rock band, The Faces (not to be confused with the Small Faces, both amazing bands). The closest thing I could compare them to would probably be the Kinks, but even that is a stretch because of how unique they were. "Ooh La La" is the best song imaginable to listen to on a breezy summer day.
The Faces - Ooh La La
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That being said though, the Pistols are simply better in my book. Sid Vicious may have been the world's worst bass player, but Steve Jones & Paul Cook weren't bad musicians. And Johnny Rotten, AKA John Lydon is a music genius as his work with the Pistols & later Public Image Ltd. shows.
So Pistols win it for me.