Peers - Ratt, Poison, Skid Row, Bon Jovi, and, yes, Motley Crue. I said "last" sex, drugs and rock and roll band. Crue peaked in 89/90 and was done by 92. Guns peaked in 92 and were done in late 93. Done means days as a currently popular act are over. Both are doing/have done well on the nostaliga circuit.
Nikki Sixx is infamous for being one of the worst bass players in a major band. Sixx had to record his parts a few notes at a time for every Motley album prior to Dr. Feelgood when producer Bob Rock made him get lessons. Nikki Sixx mimes his bass parts to backing tracks live today. Duff can play bass, guitar and drums and is well respected as a musician in many genres.
I'll give you Tommy over Adler no contest. It's closer with Matt Sorum skill wise, but I love Tommy's flair. I will take Axl over Vince since his vocal range from low register to high register is (was) insane. Both are hard to listen to live today. Mars and Slash were both great in their own right. In my opinon Izzy Stradlin is what set the two apart. He was the main songwriting force in GNR, and his riffs under Slash's leads gave Guns a fuller sound with two guitars as opposed to one, especially live.
Dr. Feelgood was Motley Crue's most successful album. It sold 6 million records in the US. Classic album. I had it on cassette. Appetitie for Destruction is still the highest selling debut album in the history of American music with 18 million sold in the US, and both Illusions sold 7 million-plus in the U.S. I think it's fair to say Motley Crue had a much longer career, but GNR was bigger if you look at both bands at the peak of their commerical success.
Then grunge killed them both in what seemed like a matter of minutes. I won't talk about that 1994 Motley album with John Corabi or Chinese Democracy. lol.