The typical MVNO model would be for Google to handle all the support. I agree that end-user support does not seem to be one of Google's strengths.
I have no doubt that the support for this will be as good.
Now, their automated side of advertising is crappy unless you're a large spender, but then that's just economies of scale.
That hasn't been my experience, particularly with this issue:
https://code.google.com/p/android/issues/detail?id=82949
Basically you have to roll a dice whether you'll have sound in voice calls on a Nexus 4 running Lollipop. 500 comments, 1200 stars, and the issue is simply closed as "wrong forum" with no other comment than "contact customer support".
I mean, I'm glad that Google supports so many camera features, as that's clearly the most important function of a Nexus 4, but at the end of the day I still expect my phone to be able to, you know, make voice calls.
Related HN discussion: https://news.ycombinator.com/item?id=8898669