It often takes me two or three tries to turn the page on touch screens and I mostly find it easier and more comfortable to use my free hand for page turning rather than reaching over with the book-holding hand. It's never bothered me and buttons were never on my wishlist. I didn't care for the "buttons" on the Voyage so I disabled them.
Now that I have an Oasis I've come to prefer the buttons. I do still find myself using my opposite hand and the touch screen part of the time though and for some reason my thumb insists on thinking the button is a rocker switch and tries to page back with the top half of the page-forward button.
