I have been using MPD for a number of years and have always found it to be reliable. Upon installing it on an ubuntu netbook I discovered a very annoying issue, any other sound causes the default MPD configuration file tends to choke out if another application plays a sound. This does not happen right away, but rather it queues up all the other audio and when loading a new playlist blasts out the queue before locking MPD out of the sound system for a random amount of time. The following fixes that issue and allows you to have multiple sound sources playing at once (pidgin notifications, alarms, etc). Simply edit /etc/mpd.conf and add in the following section before restarting mpd.

audio_output {
   type "pulse"
   name "MPD on localhost"
}