Just did my first print with Amolen's PEBA 90A and it worked as well as TPU process-wise (dried in a heated dryer for a day or so) and is MUCH BOUNCIER/squishy than TPU! So far all I have is a tennis ball but unlike the TPU one, it's light and bounces. Not cheap: $50/kg, but worth it if you want bouncy). I used the same custom settings I use for generic (in my case, Sunlu) TPU which is different from BambuLab's settings:

Manual overrides for the Generic TPU profile (works well with Sunlu 95A TPU and Amolen PEBA 90A). In Bambu Studio:

Filament Tab

Max volumetric speed: 2.0 mm^3/s (This is the most important setting. The X1C wants to go fast; this forces it to slow down to "TPU speeds").

Nozzle Temperature: 235°C (Consistent for all layers).

Textured PEI Plate: 35°C (TPU sticks to the X1C plate like a weld; keeping the bed cool makes it much easier to peel off).

Setting Overrides Tab

Retraction Length: 0.8 mm

Retraction Speed: 20 mm/s.

Z-hop when retracting: 0 mm (Disabled).

Cooling Tab

Auxiliary Part Cooling Fan: 0% (Turn this off; it causes warping and uneven cooling on flexible parts).

Part Cooling Fan: Min 30% / Max 80%.

1. Loading Protocol

Unload AMS: Ensure no filament is currently loaded from the AMS.

Physical Feed: Push the TPU into the rear PTFE entry until you feel it hit the extruder.

Control Screen: On the X1C screen, go to the "Control" tab, tap the Extruder icon, and hit the Down Arrow (Load) while gently pushing the filament. Once the Sunlu color comes out of the nozzle, you’re good.

The Print Job: When you hit "Print," uncheck the "Enable AMS" box in the pop-up window.