I agree with all above
Just to throw in my 2p worth.
Ridden loads of Duc's with various different "loud" cans. The boys in blue in Strathclyde (seriously my hat goes off to them!) seem to be the best around. They always seem to turn a blind eye (within reason!).
Spoken to loads of them in the store and this is what they say: -
"You have a loud can, you take it easy through the built up areas (high gear, low revs etc) we'll generally leave you alone. If you hoon through, you deserve all you get and we'll do you on the spot!"
"Best tip we can give is to keep on a legal number plate. We get complaints from bikers that we can't see their bikes after they've been nicked, how can we if we can't read the plate 'cause it's the size of a postage stamp?!
Plus we know your trying to avoid the camera threat, doesn't matter that it looks better. You keep a legal plate on and as long as you don't give us a load of verbal, there is a good chance we'll send you on your way"
Now folks, this is a sweeping generalisation, but i've never (touch wood) been done for having loud pipes on a bike in Strathclyde. Been pulled a good few times for various degrees of nonsense but plod always turns a blind eye to the pipes.
had a "tea tray!" legal plate on.
Loads of my mates who don't, have got done!
To me there is a clear pattern here: loud pipes + legal plate = better chance of survival!
Then again maybe i've just been lucky!