Heading off to an event this week I realised I'd forgotten to pack one of our Google Cardboards for a demo. I remembered seeing a headset in the RED5 shop in the Bullring so I dived in there and picked one up ( a VIZOR) for £25 (down from £30). Not cheap, but OK as I needed it on the spur of the moment. Build wise the headset is actually quite nice, comfortable and reasonably sturdy, and the slides that hold the phone actually work better than the suckers on the other "plastic" Cardboard we have - and essential given the rubber backing of my iPhone. The lens adjustment slides (and twist for focus) work OK, although with the iPhone the image didn't quite fill my view, so there was a bit of edge visible. But all livable with for a quick demo or XMAS present! However the big problem is that the device has no external button - the phone is completely enclosed (although a foam side lets your plug in your headphones) - so there is no way of actually manually selecting options on the screen. This is an immediate problem for the basic Cardboard demo app as it waits for you to click on the icons to launch the various demos. Nothing on the box tells you that it hasn't got a button (why would you admit to a lack of a feature), and if you don't know better you won't think to look or ask - unless like me you're in a hurry!)
When we built our Comet 67P Cardboard app we had a big debate about what to do about "the button", as we knew that some older VR viewers may not have them, and also knew that on our Cardboard it was already showing signs of failing from over-use. So in the end we decided to have "stare to activate" on by default, so that you just had to look at something for a few seconds to activate it. The settings also let you switch this off if you preferred the button method - but the crucial thing was that the app would work "out the box" even if you had no button.
Have used the VIZOR I'm really glad we took that decision. Being in High St gadget shops there has got to be a good bet that the VIZOR will be one of the most bought VR headsets this Christmas. If people buy it, kids (or grown-ups) slide their phone in on Christmas Day full of expectation, but then only to find that they can't use half the games and apps they download for it because it doesn't have a button and the apps have not been written to work "button-less", they are going to be mightily annoyed.