Setup the box yesterday and i can confirm you can get the ondemand websites to work in a sideloaded chrome using a keyboard/trackpad combo. Its a little tough to use but gets you where you need to go, im not sure if my wife will think its easier though than just using that same combo but on the current htpc. I have tried using Matt's repo inside of the Kodi app without any great luck yet. Am actually thinking about just paying for plex pass too, it looks super awesome on the android tv for live tv/pvr and really its not a whole lot of coin to pay. I currently use Mediaportal as the backend but plex is looking a lot simpler for me needs (as one gets old, arsing about tinkering gets less cool)
The box is solid though, got the main apps i need setup and chrome sideloaded, i just wish tvnz and three would come to the party with offical apps for android tv. Its not like they have to modify their main ones much... im guessing its licensing though.