As old as they are, they still put on a good show. Worth seeing. You need to know their music, though. Some guys I knew who went to the Atlanta show said "why didn't they play their greatest hits, nobody wants to hear obscure stuff..." They didn't play anything obscure to KISS fans with the exception of one track from the Sonic Boom CD. The rest was vintage and spanned the catalog.
Paul's voice was pretty messed up in Atlanta, but that was their fourth show in five days if I remember right.
When I went to see Crue at Bayfest in Mobile, Vince had laryngitis. He couldn't sing anything. It was pretty bad. Best bands I saw there were Skillet, Earth Wind and Fire and a little bit of Nelly. Surprised that Nelly completely toned his act down. Godsmack, Crue and quite a few others went full bore with the profanity. Nelly censored himself. thought that was a decent thing to do and didn't detract from the groove.