Ok, like the title says I had just bought a Sony DNF420PSBLUE Walkman. It's Awsome! It can play Atrac3/Atrac3Plus, MP3, has its own rather cool equalizer, digital am/fm/tv/weather band radio. One question though. Three of the reviews I read on the Sony Site said that the product has lasted 20 hours on one AA battery, 30-some odd hours on one AA, and another said he has gotten it to last 50 hours and stil has life in his battery. What I'd like to know is what battery the guy who had 50 hours was using? Or if someone else knows from experience. Thanks.