I've had these for a few weeks now and I'm happy with them.
I bought an original Sennheiser re-terminated with 2,5mm TRRS balanced cable from oidiosound for £40 incl. postage. Makes a big difference as I don't need to (nearly) max out the volume on my gear (either fiio Q1mk II or straight the Pioneer XDP-30R) They sell more "advanced" stuff as well, but the price/performance ratio for me is the best with this balanced cable. Delivery was by registered mail, ordered Sunday, Friday already attached to the headphone.