The duct looks scary thin, but is quite strong and prints easily on an M2. In PLA 25% filled, it only uses 10g. It mounts using the same screws and nuts that came with the M2. The more aggressive version works even better, but gets close enough to the hot end that I recommend using ABS. It is also a little thicker to resist heat deformation. No problems with either one. The second one delivers air more precisely where it is needed, but can result in more of a quality difference between front and back of the printed object due to uneven cooling, so I prefer the less-aggressive model. Either one is much better than the raw mounting of the fan as MakerGear does it.
Incidentally, yup, that is it being used to print a copy of itself in the seventh image. Why? Well, I printed the first one before I had the attachment and the second one (as you can see) after. The second one is a much nicer print... which was the whole point of doing this. I actually have two M2s, so neither copy of this mount will go to waste. ;-)
The last photo is of http://www.thingiverse.com/thing:690176 , printed on my MakerGear M2 after installing the ducted fan mount. This is a tiny wine glass, with a long stem that's around 2.25mm diameter -- which would have sagged and probably caused a print failure with the standard fan mount. Printed in white PLA at 0.25mm, 8% fill (there's fill in the base, stem, and lower portion of the cup), 50mm/s.
BTW, the third (latest) version is the one shown in the second photo.