From personal experience, I went to a Babyshambles gig a few years ago and Pete Doherty was completly off his face on heroin. It was really bad, and it ruined the whole show. To be honest, it almost put me off the band. He couldn't remember most of the lyrics, and mainly just wondered around the stage, and falling over.
From not-so personal experience, my uncle went to Latitude festival in 2006, and, him being a hardcore Manics fan, went to see Nicky Wire play his solo gig. He was completly drunk. However, my uncle said it was really funny, but he expected just a little more music. He said it sort of turned into a stand up comedy routine. I saw it on youtube (below) and laughed so hard for at least half an hour, but then thought 'Is it fair on the fans?'
Nicky at Latitude 2006 [from Youtube]:
Your thoughts and experiences?

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If God were human he'd be James Dean Bradfield
And if God's wife were human she'd be Nicky Wire.

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