JokkerI'm pretty sure the K7XXs are better. I'm surprised the THX00, HE350s, and K7XXs were all dropped at the same time. That's like the Holy trinity. The AKGs are priced low because they're made in China, not Austria like the other AKGs, and the 600/700 line have been out for a while. Price drop was inevitable, also securing a large drop like this as a bulk order helps.
From Zeos' review, and me having the K7XX, and the SHP9500 and HD598s he compares them to, you can't go wrong with the K7XXs. Don't go looking for bass though.
BiggestMacIt has been answered, Zeos said K7XX have more bass and a more comfortable pair of ear pads with similair soundstage. I am considering dropping out of this drop as they are too close in sound signature to my SHP9500.
6EQUJ5Depends on how many headphones you've got :-) if you have only the 9500 then sure go to the other direction and grab a DT 770 and enjoy both worlds. But if you have like 10 or 15 pairs of headphone from all types then why not add this baby's to the pile.. They will look so fine with the HM5's angled pads mmm I wanna lick them right now..