My first modern era headphone was the K702, which I parterned with the Schitt Asgard. From there I progressed to the HD800, which I was using with the Schitt Vahalla and later with the Sennheiser HDVD 800. As much as I enjoyed this, when the AKG K712 arrived I bought it and the HD800 saw sporadic use. I later sold the HDVD800, and am currently selling my HD800 on eBay. When the K812 came out, I waited several months to check out the HeadFi reviews, then promptly picked one up. This headphone is far and away superior in every way to any previous K series design. If you're really interested, you can order these from Amazon and have a 30 day return per their policy.
I eventually sold my Schitt products and teamed the K812 with the Phonitor 2 and I have finally found my endgame system, (at least for now).