I bought some Fiberlogy 40D flexible filament for my first attempt at Flex. I used PrusaSlicerβs builtin preset and printed it on my MK4 w/o input shaping. Most of it turned out well and the bow area has a nice flex. The surface has a nicer feel than PLA or PETG. But there is a a defect on the front. I think the angle was too much for the filament or preset. Also the text β3D Benchy" on the stern is less clear. (½)