does anyone know? 1. Are there any diferencies between NW-E407 & NW-E507 beside FM tuner? I don't listen to radio so I won't buy NW-E507... unless there're some more differences between these two models. 2. do they go with USB2.0 or with USB1.1? 3.) Tracks leading/ending silence - many of my albums are recorded as "one" track - without gaps between each song. Can I play them that way on NW-E407/NW-E507? Thank you in advance for answers.