Yes I was one of the lucky ducks who got an invitation to Google Inbox. Coming from a GTD background, I was generally distressed that the only context you get to choose from is a physical location. This is pretty handy. The only other way to sort tasks is via date. So the vast majority of my tasks which have to do with contexts rather than places or dates are not processable using Inbox's current setup.
I have left a suggestion that you should be able to label you email and reminder tasks with more than one label. This will give me the ability to check out all my tasks tagged "@Calls" for example and then differentiate between @Personal @Calls and @Work @Calls.
If this is available in an update, I reckon I will give it another bash. Otherwise I will keep using Zendone.