P990 is a smartphone, while W880 and S500 are not

With P990 you can use a lot of programs which allows you to have a complete device, but is big and not sporty

W880 is a great phone but doesn't have radio

S500 is a good phone, but if you're interested in listening to music and sports you should buy W580 which is an S500 with the walkman menu and some functions for fitness like counterpass (I don't know if this is correct in english), so I think this device is eccelent for your friend