The BMG clone (clear) dual-gear extruder is now installed using a printable mounting plate. There didn't seem to be a clear statement as to which was the filament "input" port. I found it was installed both ways in the wild, and from observation I did not see any difference it would make. I did observe that the the bowden coupler closer to the release-lever was pressed in and not easily removable. The other one was simply screwed into an aluminum fitting. That was the one I used as the output port. Also, this was nice because I didn't have to invert the direction of the stepper motor. The recommended E steps value was 415, but after calibrating that parameter, I found that 427 was the number for this machine. Other than that it went smoothly.
The results certainly are no worse than the previous single gear extruder. Both models looked good (printed at 0.2 mm). But of course I was looking for more than that. The model produced by the original extruder is on the left.
I will say that, yes, it does yield better results in places. Using the benchy model, the bottom first layer came out better. The back lettering was a little better. The top of the deck came out nicer. The light is reflecting from it as you see because of that nicer surface - not because of the placement of the light. The top of the bridge had a nicer surface, as well as the inside of the cargo box. The rear window was a little bit more rounded. The layer lines looked a little more precise.
So, I'd have to give this extruder a passing grade and I'll keep it on the machine. At this point on this type of printer you aren't going to get many more eye-popping improvements. But for the small details, yes it does work better than the stock-style extruder.
If the Zesty folks get to the point of shipping their product, I'll do another face-off between this extruder and that one.