Parent is correct about DC Rainmaker. He's very thorough and accurate.
For tunes, I recommend an ipod shuffle (the ONLY apple product I use). It's perfect for sports, it's VERY cheap, the battery lasts a long time, and if it can handle my sweat it can handle anything.
Your garmin watch should not be having these problems. A 3 hour battery life is either a dud battery or something weird wrong with the software. Try a full reset. Regardless, you won't find anything better than a forerunner.