reubadoobim not asking for a comparison of specs as they're essentially the same. I mean how do they actually sound in comparison....are the K7XXs supposed to be warmer sounding than the K701s?
AllenPK701's according to most reviews have harsher highs and have a colder sound. Imagine if you are on the edge of just a little short on bass and highs are just a little too sharp, the K7XX's are meant to "fix" that (a warmer option).
In my head that's probably what's going on, the bass have great authority and is well presented, but it is below the borders of what would be needed for a good movie experience. Also I find noise above ~18kHz much more noticeable compared to my desktop speakers (so crappy youtube videos are a no-no), but on well mixed quality recordings you will get the full benefit of the sound-stage these cans produce.
As someone else mentioned acoustic guitar (that's recorded well) sounds amazing, I recommend listening to "Beyond the Knowing" from buckethead on the K7XX's. It really worthwhile to hear those guitars as close to reality as possible (at least for me).