Thanks for the input folks!
One more spanner in the works, If music has been purchased on itunes, then of course there is no solid product to prove it has been purchased, yet as anyone with itunes knows, it is possible to create a playlist from purchased music, which can then be burnt onto disc. Is there any way round the whole legal side of things?, as swapping a disc of music bought on itunes is much the same as leaving a bought cd, its just not in expensive packaging!