I have been paying for the protection plan for my iPhone 8. The battery life deteriorated significantly, so I asked for a replacement phone per my plan. I received a refurbished phone that works even worse than my old phone (battery life low, cannot receive text messages, screen freezes repeatedly).
I had the same experience a few years ago when I lost my iPhone and received a crummy replacement phone through the protection plan. I thought that was just bad luck, but now I realize these refurbished phones are not guaranteed to work.
I realize that Verizon will keep sending me replacement phones until I get one that actually works, but that is a huge burden for me: I have secure software on my phone (I work in a hospital), and every time I get a new phone, I have to work with my departmental administrator (who is very busy) to get the software re-activated on my phone.
I am going to buy a new iPhone out right from Apple and cancel my protection plan moving forward.