Quoting this for emphasis.
JAHrig, Montins., and Landis are all completely on point and I agree 100% from a mixing/sound work standpoint. HOWEVER, it seems the OP is not actually doing any mixing, but simply wants a quality sounding headphone to showcase his work. Given that he will be using the headphones to solicit prospective clients in a loud showroom, I would say that Quiet Comforts would be the best route to go because of the noise canceling tech in them, in addition to the great sounding (though not accurate for mixing) acoustics.
Totally unrelated, have any of you mixed/monitored on Ultrasone headphones? A couple months ago, I needed to do some editing away from home, so I purchased the Pro750 and have been fairly pleased with them so far.