One should not knock songs that do (mostly) with only three chords. I like the jammy-cobbled-together aspect of the song - the opening riff that Slash used to check his tuning, the country'esque three chord verses Axl came up with, the chorus which sounds a bit like they made it up on the spot in the rehearsal room (bit of Dokken in there) without too much thought about which key the original song was and, finally, that ingeniously awkward key change for Slash's solo, most likely because he had issues soloing in other keys than E minor (and certainly not D major!). Put together you have a charming mix and a recipe for a hit.
PS: And I know how Duff always belittles his own bass playing (for no valid reason IMHO), but you can do worse than having written a melodic intro bass line that becomes so much part of the song that even a Bavarian beer tent band uses that line for its horn arrangement. Geddy Lee - with all due respect - has never had one of his bass lines covered by a Bavarian beer tent band, so there!
