Just tried Ninjaflex on my Makergear m2 and it is a bit tricky.First off you need to rig up a gravity feed at least if you have a direct drive like the M2, it was too stretchy to be pulled. Also had to adjust the tension a bit. Used the .5 nozzle, 10mmS , no retraction and the center temp within the manufactures range. Neat stuff, make me some stepper motor dampers and it worked great!Good luck