Support was terrible. I called a few times letting them know there were dead spots all over SF and Berlin. In my hometown, I struggled to get coverage every once in a while, too. Nobody else, even on the cheap platforms, had any issues.
I called twice. One time I was disconnect and could never reach back through again. The other time I was told that they were "sorry I was disappointed" and that they'd help me cancel my account if I wanted. I wasn't rude or anything - quite the contrary. I had never had such a weird or degrading phone call like that before.
Oh and the spam calls. I had tons of them, some days I'd have five or six throughout the day. It was insane. I posted on the subreddit for support and they told me "well they use the back-door numbers (or whatever, I don't know how phone technologies work) so there's nothing Google Fi can do."
It was insane. Avoid.