I listen to a lot of music (from all genres). I only purchase/download full albums (even if most of the songs are not very good), and only listen to at least 196k MP3 (most are at least 256k or higher). Some are Apple Lossless (converted from FLAC). And throw in a few discographies in there and all of a sudden you have 350GB. I've discovered that I add about 50GB/6 months.