I read on mine every day, everything from developer documents, PDFs, novels in iBooks and Marvel Unlimited. They're all awesome on the big screen.
I use it in portrait and landscape, for portrait I started putting my hand across to the furthest away side of the iPad and I rest it on my forearm, rather than with my old ones I held it by the edges. I find it very comfortable that way.
I've still got smaller iPads, other tablets and my trusty Kobo H2O, but nothing beats the big screen of the Pro.