The muted red polyterra feels like terra cotta a little. The matte additive is really dense, so parts feel heavier than other parts (polyterra PLA and PETG are the two densest non-filled filaments I've used). Whatever the additive is, it also increases the strain to failure by a lot, so it's less brittle.
My only complaint about polyterra is that it is not as good at layer adhesion as the regular PLA/PLA+. I can't push my printer to the limit on speed without getting a part that wants to separate at the layers, so I have to slow the print speed and slow the fan down, and I usually print a little warmer.
I'm finishing up my first Polyterra PLA+ print right now. It has less of the additive so it's advertised as a satin finish more than a matte finish.
For what it's worth, I just bought my first 3kg roll of filament for a big project, and I chose polyterra PLA in black.