wifi

Is a car great for driving? 

With minimal info, we can't tell you a lot. do they work, yes.

do they work great for all? Not always because of many variables such as home size, home material, wireless interference, etc. 

Just asking if they work great doesn't mean we can tell you that yes they'll work great for you. They do work and for many they do work great. 

Are you asking about the Model: A6150|AC1200 Dual Band WiFi USB Mini Adapter listed in your footer?

That has nothing to do with wifi extenders, except as a client that can connect to one.