However, 6.3" just seems like a deadzone. Too big to hold in a hand and use effectively, unless you're Shaq, but smaller than a 7 or 8" tablet like the Nexus 7
Don't forget that the correlation between screen size & device size is not neccessarily linear. Samsung managed to increase the screen size of the S4 (over the S3) by 1/5 of an inch while (slightly) reducing the phyiscal dimensions of the phone.
The Nexus 7 has a massive bezel, these devices do not & will be smaller than the 0.7 inches you'd expect placed side-by-side with a Nexus 7.