I have owned and used the 12.9″ version of the iPad Pro since the Summer of 2016, when I first purchased a used first-gen model. Despite trying out the 10.5″ version that came in the Summer of 2017 and then the 11″ version that arrived the following Fall, I have continued to use the larger device over the next two generations.
While I have reasons why the 12.9″ size works best for me in practical, everyday use, I can’t help but prefer the 11″ version from a perspective of pure hardware build. It’s just a great balance of size, weight and capability.