I abandoned Fi after a trip to western Europe, where I was billed for 6 GB of usage in a single day on one of my data-only SIM cards, despite that the device the SIM was installed in (a 4G hotspot) registered only 200MB of usage that day.
Support was completely unhelpful, and after escalation reported back that the Fi team has zero visibility into chargebacks from their carrier partners and ergo could not diagnose the cause of the usage discrepancy. The lack of accountability on Fi's part, in addition to various annoyances (handset tendency to select Sprint coverage despite poor performance; handset tendency to override manual carrier selection to the detriment of service reliability; generally worse reliability and coverage than my previous carrier) led me to move back to Verizon. I pay an arm and a leg for my service, but at least it's highly reliable and available.
Support was completely unhelpful, and after escalation reported back that the Fi team has zero visibility into chargebacks from their carrier partners and ergo could not diagnose the cause of the usage discrepancy. The lack of accountability on Fi's part, in addition to various annoyances (handset tendency to select Sprint coverage despite poor performance; handset tendency to override manual carrier selection to the detriment of service reliability; generally worse reliability and coverage than my previous carrier) led me to move back to Verizon. I pay an arm and a leg for my service, but at least it's highly reliable and available.