The tips work best with medium to low top speed propellers ranging from about 8" to 35" and when the air is traveling at less than ~10mph into the propeller in the same direction that the propeller pushes air. This is why they are often used on drones designed to produce static thrust efficiently, but not fixed wing aircraft. The entire purpose of these is to minimize tip vortices and outside any of these parameters the vortices can not be fixed or are not large enough that a tip can help.
As the x4 is pushing the limits of the thrust a 22" prop is capable of giving and it has over 10 mph airspeed, prop tips wouldn’t help.