This works really well, but it's a challenging print. If you are going from the stock duct, this hangs much lower. I've replaced the clips holding the glass bed with blue painters tape, this removed the crashing problem. The down side to this air duct is that it visually obstructs the print from every direction, makes it hard to see what's going on, especially on smaller prints.
MG Chemical PETG
This took a number of tries to get a good print. Go really slow on the first couple of layers, if the air ducts don't print right they will be clogged. If you can get the ducts on the surface to print right, then the rest should be easy.