I am thinking you aren't getting a lot of traction on this question because nobody can say for sure.
Generally, no surge suppressor is perfect. They help and certainly using this would be a very solid way to gain some level of additional protection over just using a standard outlet. A whole house surge suppressor is a better way. Using a large, quality suppressor is a better way, then extending power to the projector/tv location is a better way.
Given enough of a surge, you will never have a perfect solution.
I personally use a few Surgex units in my home and I protect my displays by extending power from the Surgex to the displays.
But, if this was really problematic, and I didn't want to have a bulky and expensive unit behind a display, then this wouldn't be a bad option. For the money, it may be a very reasonable option. Not worthless, but not great.