This is an amazing design that definitely helps direct airflow more uniformly and efficiently. I reduced my fan to 40% after using this, and noticed more consistent results than with the stock fan redirector. However, even with the short version, I only had about a millimeter clearance for the tip of the nozzle, which is a micro swiss and should be longer than the stock nozzle (meaning, I should have even more clearance). Because the ring is so close to the bed, visibility was reduced significantly and if a piece of stray filament sticks up it snags badly on the ring. I applaud the author for the ingenuity, just be aware of the pros and cons of using this ring if you decide to add it.
Printed with glow in the dark Hatchbox PLA.
I tried .1 and .2 resolutions, .2 gave me a stronger defense against snags on the air nozzles and was otherwise almost indistinguishable from .1 resolution.