I previously had a pair of Sony noise-cancellers.  The big downfall of the Maxells are the battery pack.  It's about half-way down the cord.  If you use them at a desk and move much, you'll constantly pull the pack off of the desk and it'll fall with a sharp jerk to your headphones.  The Sonys only used a single AAA battery but the Maxells use two.  So, Sony was able to put it in a compartment on the headphone band with no aggravation.  Oddly, the Sonys seem to have much better battery life for me.  The Maxells do enclose the ears much better to help block sounds, but they do start to hurt your ears after prolonged use.  If you wear them for hours at a time, the similarly priced Sonys are easier on the ear.  I'm not wild about the way the Maxells fold up, either.  The Sonys kind of spin in and make for much flatter storage.  Another problem with the Maxells is a loud creaking sound from the plastic.  Often just moving your jaw seems to produce a loud plastic-on-plastic noise that comes through quite loud.  With a slight re-design, Maxell could have a nice set of headphones.  Wait until then or try another brand.