Project Fi uses the T-Mobile, Sprint, and US Cellular networks. I doubt they'll ever get AT&T or Verizon, since those two networks are so big. Recent commercials on TV from Sprint say they're just as good as Verizon (which I doubt), and the T-Mobile CEO has been pumping out some cool promotions, so maybe it's a good time to think about Project Fi.
One of my good friends has Project Fi, and it's very straightforward. The billing/payments section is super straightforward, unlike Verizon, which is super confusing.
So I'm saying goodbye to Verizon's unlimited data, and I'll see how I feel with limited data. If you have any tips on how to reduce data usage, let me know, because I've never really had to worry about it.