You can enjoy pretty much any type of music on the m80's regardless of recording quality, age, ect.
However, you will really LOVE listening to great recordings and appreciate them that much more. This may lead you to be selective in what you listen to for critical listening sessions or demos of your system. I don't think it will stop you from putting your current collection to good use though.
Completely agree.
I also agree with FredK comment. If you're looking for a deeper bass due to the type of music you listen too, maybe the M80s would be a better choice.
