Dave, I don't think that any music that is free of PRS is a problem to play - it's by its nature unrestricted, especially of it's been provided by the musician.

On the topic...

The UK radio station where I do my programme is set up to play mp3s if necessary but I often cringe when I hear some of the results, especially on music with lots of synth sounds as nasty effects are often more apparent.

Having said that, not all music suffers from the effects of mp3 compression in the same way and I have used the format when I needed a track quickly , usually for an obituary item or for a soon to be visiting musician who's new to me and where I haven't got an album available. If I can download from iTunes or whatever then I use the file as long as it passes the 'ear test', ie. I listen to it and decide if it's technically up to it.

The tolerance is reasonably high because in our sort of music, the content is often more important than the high fidelity, but I always transfer it to CD format for transmission and in doing so have an opportunity to tweak the track if there's some aspect that can be improved (rarely but occasionally possible).

I don't like mp3 but when you haven't got a budget for buying CDs you sometimes have to compromise. I think I've got away with it as I select with care and monitor beforehand - and none of my discerning colleagues have commented as yet. Also, quite a few of my listeners 'listen again' online, which brings its own quality problems. But they don't seem to worry.