Qidi X-Max jamming with Ninjaflex Ninjatek TPU

[curious aardvark]

print flexibles slower - NO slower than that :-)
15-20mm/s
Possibly evem down to 10mm/s for the really bendy stuff/. On the positive side you don't actually need to heat the porintbed up and the first layer can go down at 100% print speed - which helps for larger prints.

It might also be worth taking the extruder apart and seeing if you can insert a short length of ptfe to make sure the filament can't escape the path.
All my extruders - bar the sapphire pro - have been modified with ptfe tube. Unfortunately the bmg extruder on the sapphire pro, can';t be modified and is absolutely crap for flexibles, they manage to escape sideways. It should not be technically po9ssible - but nobodsy tells the filament things like that :-)
And if it can escape - it will, a bit like sheep :-)