I know it goes in an electrical box.

From the pic on the Ethereal piece, it looks like there are 3 exposed metal terminals on the back of the outlet connected to the pigtails of the three wires in the left pic. Maybe I am making a bigger deal out of this but my feeling was a potential for the bare ground wire to contact one of the non-ground terminals when pushing into the outlet box. If the wires connected to side screw terminals or pushed in the back, like a standard receptacle I wouldn't have second guessed. The snapav one has 3ea metal points exposed on the back and had an issue once with shorting out when using in a metal outlet box, which is what has to be used in a versabox. Versabox was remote mounted in closet due to stud spacing behind TV and used powerkit from TV location to versabox.

The Midlite piece I linked has the romex sealed to the body of the outlet.