Hi guys, it seems smooth :)
But the "l'Aigle", in France, has rubber band arms since 2003, it's not so new.
This is their flagship arm: http://shop.laigleparis.fr/index.php?id_product=69&controller=product&id_lang=5
And now the isoelasticity can be adjusted without tools, so I guess no need to remove or add rubbers (unless perhaps if you go from DSLR to a much heavier camera - like the GPI Pro arm canisters have to be changed).
Rubbers are pretty smooth and quite. I have an older l'aigle rubber band arm. The only thing to be "careful" about when operating is extreme temperatures. You need to readjust the elasticity. The cost of changing the rubbers is near zero. L'Aigle for example guarantees them for 10 years... so you can change all the rubbers for free before that.
(P.S. I am not working for l'aigle (!) and their systems do have flaws, but also interesting innovative concepts. Twiga seems to have taken the same approach with their new arm, interesting :)