I didn’t have any problems getting tpu or petg of the pei sheet. I’ve used tpu only for tires so not much surface to stick. Petg needs a bigger nozzle distance and if this is correct set it shouldn’t be a problem. But I’m printing mostly technical stuff and parts for printers.
@Richard_Rohan Yes I find things with a small contact area are fine with petg. It’s when you print something nice and large and flat that the fun begins if you don’t coat it in PVA or similar first…
Ive only ever used PEI and i have no issues with it. I print PETG on it all the time and it hasnt taken any chunks off of it 