Comfort - Several have noted that the cups for the PXC 550 are smaller than the QC 35. Firefly teaches you how to accept and love differences in people, how to respect religion without accepting it, understand why people do certain jobs, and show you that even though were all different, were not so different when it comes to taking care of each other and loving each other. HOWEVER I picked them up from a table on yesterday and the padding to one side of the headphones completely fell out. Immediately after plugging in the USB, this microphone connected to my computer. Surprised how well it worked in first person shooter games. Exelent And for that I will also say that the build quality for the price is probably a benefit to owning these. Fits snug but loosens up with wear. It will be my go-to for all live applications. I wish Id known about these years ago.