OK, some might turn out to be utter fools and shameless charlatans. Others might have bad breath, bad hair and a bad attitude.
Some might even become your anti-hero before very long.
But when it comes to the gods of rock and the main men of metal it’s the exception, rather than the rule, if they don’t turn out to be top blokes.
Take Alice Cooper. As a kid I watched him steal the show with his cameo in Wayne’s World and a decade later I landed on his tour bus.
Star struck? I was shaking like the proverbial leaf. But then you should have seen my mate.
Happily assuming the role of Garth he sat, open mouthed and speechless, for half an hour unable to come to terms with his audience with the Coopster.
And yet during those 30 memorable minutes one of rock’s greatest living legends proved himself to be the perfect gent and a great interviewee.
Happy to talk about music, what he really wanted was to chew the fat on golf, politics and travel.
And talking of politics that was a subject close to the heart of David Coverdale the first day I met the Whitesnake crooner at his best pal’s Newcastle hotel.
There to promote his new solo record the conversation quickly moved to the state of the nation – a country he quit for North America some years ago.
Another Teessider to swap the UK for a country pile on the other side of the Pond is Free cum Queen frontman Paul Rodgers.
And there is another perfect example of why it’s a kind of magic when you meet your heroes.
Backstage at Newcastle’s City Hall the Voice made all his guests feel at ease. He broke off from a family get-together in his dressing room to talk all things rock.
And he spent a great deal of time talking to the nurse who had looked after one of his closest friends during a serious illness.
This is a man who has fronted some of the biggest bands in the world, a man who has millions in the bank and a man who probably needs a few early nights.
But like Cooper and Coverdale there is a reason why Paul Rodgers is a rock hero. And the more heroes I meet, the better.