Not a definite answer but it may help you.
For aesthetic purposes, I tucked my modem/router nicely at one corner of my house. With this setup, I barely have wifi signal at the farthest corner of my house - the corner diagonally opposite. Adding this unit allowed me to have wifi connection at this corner - not full strength but very good. And don't expect to get the same speed as the router. I chose to connect using 5G and it is about 50-60% speed as the main router.
For reference purposes, my home is 2600 sq ft, 9ft ceiling.
I have since repositioned my router to be at the middle of the house which enables me to have good wifi signal from the basement to the second floor.
This unit has now been relegated to the garage to extend my signal across my driveway.
Hope this helps.