Lighting & Studio flash modifiers

I've done a small comparison between the 3 flash modifiers that I currently have. I've tried to get the exposures and the framing the same in all pictures, though I moved the camera a bit when I installed the last modifier.

I hope this might help you decide which modifier you'd like to use or skip.

the gear: Sony A6000 + FE 90mm f/2.8 + Godox V860IIS (mounted on the camera hot-shoe) Manfrotto X190PROB + Junior Geared Head + unknown Chinese manual macro rail.
the settings, these are the same for all 4 photos: sync. speed 1/160, aperture f/8, ISO 100, focus at MFD, flash zoom 20mm.
I had to change the flash power for each modifier. all photos edited in Camera Raw, with the following corrections only: exposure -1EV, daylight WB and lens corrections applied.

first photo, flash only, 1/8 flash power:



second photo, using a modifier similar to this one, 1/4+0.7EV flash power:



third photo, using a modifier like this one, 1/4 flash power:



fourth photo, using a modifier like this one, 1/4+0.3EV flash power:



as Dalantech pointed in another thread, the apparent size of the light source makes a big difference. the 4th modifier is the biggest of the 3 and provides the softest light. as the modifier is not far enough from the flash, it doesn't fully diffuse the light and that produces the specular reflections.