I was sold an in-line surge protector for my motor home because of surges in RV parks. It cost me several hundred dollars but I felt that I needed the protection.
We ended up having a lightning strike 50 feet from our coach and it fried the surge protector but all my on board electronics were saved. The building next door did not fare so well. They lost everything that was plugged in.
I am not so confident about the surge protectors I have purchased from a major electronics outlet. The salesman did confide in me that the unit may only have so many “breakers” and you do not know when they are used up as there is no way to observe them. Great.