Works fine for me. I've had it for 5+ years and yes, there are dead spots, but all cell coverage has dead spots. My Verizon friends have dead zones, sometimes in the same places and there are times where my coverage is great and Verizon is weak or dead. Likewise, I've had the complete opposite, so it depends where you are and need it the most.

I have no plans on leaving Fi, is cheap and works for my needs in the NEK.