I'm going to be doing a lot moving in the next couple of years, so it's time to toss out the z-5500's, and go with a 2.0 setup. I'm torn between the M-audio AV40's and Swans M200mkII. I'll likely be using my headphones quite a bit (Grado SR60's), which is why I'm slightly leaning toward the M-audio. Does anyone know how the amplifier on the AV40's is as a headphone amplifier, or if it makes any difference at all? I think the swans may be better for everyday listening though since they are not "studiophile" grade. Any input would be greatly appreciated. Thanks.