Just 2 more text sizes seems like a small thing, but having one between Small and Medium makes a *big* difference to me. Back when I was reading with the 650, I was actually using Calibre to scale fonts on books to get a comfortable e-ink reading size. I don't miss those days
The T1 Zoom feature is also very very nice if you have books with high quality images, such as maps, or geneolgy trees, as comon examples. Alas, most publishers shrink the image sizes until all detail is lost.
I also use my T1 as just a book reader, and have never suffered a crash or needed to reset the device. However it's obvious to me that the software was rushed out the door in an an unfinished state... If you try to select a range of text that extends near the bottom of the screen, you quikcly realize how little actual testing was done. Not to mention that actually trying to use those new optional fonts is.. quirky at best. (And Sony knew this when they put the product out, they even mentioned it in the manual somewhere.)