I kind of thing if you have all your senses working fine, you should use them to your full potential. I listen to music in the car, cos lets face it, I'm hardly vulnerable in a vehicle with an NCAP 5 rating, and, living in London, I spend most of the time 'parked' in the middle of the road, between 75,000 sets of temporary traffic lights.
On me motorbike and bicycle, I really like to be as alert as possible, and if hearing what is going on around me makes me safer and less likely to die, then great.
However, it is also down to personal choice. If you decide to listen to music, then your riding/cycling should be adjusted accordingly.
OH, and if I had my collarbone broken then I would be livid at having to miss months of work and thousands of pounds worth of income to only be compensated £515 (probably less)