I don't use it as my main mp3 players for 4 reasons:
a) battery drain - if I listen for 6 hours, the battery is practically dead
b) the volume output of the Desire, is to be honest, very very weak meaning that even if I crank up the volume, it's still not enough when using proper headphones or earphones (which tend to use a larger power draw leading to lower volume still)
c) there's no built-in equalizer and the standard output is unbalanced leading to dull sound. PowerAmp has a built-in equalizer but since I also use Spotify which does not have one, it's pretty annoying.
d) every time I get a notification, the song halts and the sound plays instead. Since I get many notifications, this gets annoying very quickly.
In short, it's not really a great mp3 player. Much better to just pay a mere $50 for a Sansa Clip Plus which is tiny and lasts 10+ hours and has a far superior output - both sound quality and volume level.