Pros:Excellent sound quality. Extremely comfortable even at long listening intervals.
Cons:Cord is not replaceable.
Ears can get warm after extended use
The Bottom Line: In my opinion, these are the best headphones you can purchase for $60 from any supplier.
I've been using my JVC HA-RX900 headphones for approximately a year now and continue to remain impressed at these headphone's sound quality and comfort. As a replacement to Sennheiser Fusion 500's, I'm completely satisfied.
These headphones have a response range of 8-25K Hz using 50mm neodymium drivers attached to a "ring port" assembly to improve bass response out of these large drivers. Full size headphones of this type normally have 30mm drivers - the larger drivers in the HA-RX900 allow crisper bass reproduction without degradation. The headphones weigh approximately 12 oz less cord which is well supported at the apex of the head by the oversized support strap thereby making these units feel nearly weightless. Cup pressure is adequate and provides modest isolation thanks to the conforming leather/foam pads. Nominal impedence and drive power ratings allow for excellent sound quality with only moderate drive gain in modern portable players. Of course the best quality will always come from more significant power sources, such as an A/C receiver or a PC soundcard with effective grounding and EMI shielding.
These headphones feel much more expensive than they are - wearing them for long periods of time is very easy - I have not once experienced discomfort or fatigue wearing these headphones. The sound quality is near perfect for this class of headphone. Bass is very pronounced and takes up significant portion of the soundstage. Normally this would be a negative, but the JVC HA-RX900 pulls this off with excellent midrange response and explosive high-range capabilities that allow the subtler elements of music to shine through beautifully.
Update - 11/4/2012
I am incredibly happy with my HA-RX900's as they continue to get better with age. I now primarily use these headphones for listening to lossless audio on my desktop PC via a Creative Soundblaster Xi-Fi Titanium soundcard. With continued use, the soundstage continues to become better defined and the bass has become quite literally perfect for listening to rock and pop with some minor EQ adjustments. One defining property of these headphones is the lack of upper frequency distortion combined with intense and perfectly timed bass to create an auditory illusion of lower volumes than actual. These headphones can be run at very high volumes without causing discomfort for lack of the tinny resonance present in many other headphones at similar gain levels. This property is consistent with fine speakers, not $60 headphones. Absolutely amazing.
I believe it also important to compare these to the currently popular "Beats Audio" headphones which are purported to be of high quality and are priced in the stratosphere. The JVC HA-RX900 headphones blow away even the most expensive full size "Beats Audio" headphones in my opinion based on a side by side comparison of both. Anyone who spends $300 on a "Beats Audio" set over the HA-RX900 is out of their mind. The JVCs aren't "a little better", "moderately better", or even "much better" than the Beats...they are nothing short of worlds apart in sound quality, comfort, and of course value.
If you are looking for full size headphones to listen to rock, pop, hip-hop, jazz, or R+B, these are the ones to purchase, bottom line. You need not spend a penny more.