If it matters to you Visible had terrible ping times for data...it's very low priority within the Verizon network.
MINT might be worth looking into...you do have to prepay international usage since plans are typically prepaid to get the best deal, with unlimited data at $30 a month on a 12 month prepaid plan... T-Mobile towers, rapidly improving in the US with sprint getting incorporated, and great overseas....
Coverage has been about the same as Google-fi, cost is less, depending on data use.