Still keeping the Sennheiser brand is interesting risk on both sides. For Sennheiser, if the devices get worse, they will suffer. If the products get better, Senn gets the credit. Makes sense as I would likely never even look at Sonova headphones in the crowded prosumer market. Hope this improves their quality that has slipped in recent times. I know their pro wireless mics have suffered recently, have had to replace a lot of the ones we installed with Shure.
Love my HD 800's. I swear they're some kind of alien tech. Just phenomenal soundstage, combined with the CMSS 3D off my Titanium HD they upped my gaming experience to a new level of immersion. I hope the brand can maintain this kind of quality moving forward.
Consumer markets are fickle and difficult to navigate. Strike the right product at the right price and you can print money (the iPhone). If you make a good product and can't convince consumers it'll change their life you'll not likely make much (Ronco food dehydrator). I don't blame them for the move, but as a consumer it makes me sad. Sennheisser has a hell of a name and if you're under 70 you've likely never heard of Sonova.
If you're going the HD8XX route, you're going through Drop.com initially for support; not so much Sennheiser (or Sonova), as Drop is the "middleman".
In any case, if you buy an HD800/800s via Amazon (or some other retailer), your return policy could be pretty good (depending on retailer, as usual).