Red Hot Chili Peppers
We've seen the Chili Peppers twice before in Guitar Hero (both 1 and 3), and yet their funk-inspired music has so much more to offer. The group has been churning out infectious grooves for nearly two decades, spanning several guitarist, and is perhaps the most distinct sounding group on our list. They also popularized funk rock. What's more, the bass riffs are just as inspired as the guitar licks (a double whammy), and there's an endless stack of fresh material to choose from.
Essential tracks we want to play: "Give it Away," "Warped," "Soul to Squeeze," "Hump de Bump". HONORABLE MENTIONS: While Metallica technically equals others on our list in terms of sales, and Nirvana fails to meet our cited qualifications, the former has a reputation for being publicity douche bags, so I picked the latter. AC/DC was also strongly considered.