def leppard HAS EVOLVED TOO......they were pretty "standard" till 1992 with the excellent adrenalize....in 1996 they tried to go grunge, they had a big flop but the album was completely different from they previous album, they came back in 1999 and again they "re-styled" themselves and their last album has the perfect mix between old and new sound...so you can't really say leppard has not evolved....they did at least as bon jovi did......

I said it few times already...in U.S. def leppard have sold much more records than bon jovi did.....even after their "big era" def leppard between 1992 and 2005 sold more than jovi