Bought all games digitally, 4 of them being available physically (Ryse, Fifa, Battlefield and Forza). I don't really like selling games, and because switching between Xbox Stores is possible on the One I can buy games on the LESS pricey American Store.
If the prices were the same I'd still prefer digital, it's really handy (and fun! Yes, I'm a Kinect-lover :P) switching between games within a second especially when you're kinda moody or friends suddenly come online, and I don't have to worry about my discs when my little brother is playing. Plus, I don't feel limited by DRM, heck I never even noticed it.
But yeah, I prefer digitally mainly because of the lower price so were it more expensive, I mean 5/10 € is something and it does add up to a big sum, I'd go all retail.