+ Console mode for Android games via HDMI
+ Brilliant streaming capabilities (eg: PC> Shield> TV> Twitch)
+ OTA update to Android 5.0
+ Super Stylus Pen and Dabbler software
+ Shield Hub incl. Grid from early 2015
Except for a few minor teething problems when wireless streaming of PC games, which was resolved after 1-2 reboots, the Nvidia Shield is imho absolutely ingenious tablet. After 5 years, iPad finally something really new and innovative, which does away with all the restrictions, prohibitions and limitations of competitors. The only point is the teeny-weeny bit longer to load when switching to the console mode or when booting.
Since Lollipop (Android 5.0), it runs much smoother again. The Shield controller and the built-in touchpad Couch Surfing makes first real fun. Even with less optimal sites or apps manages the operation without much fumbling.
A look for when buying a cover times exactly the products. Since there are third-party would be more favorable, offer more colors / designs as well as a protection for the back, where it absorbs completely the Shield. So the cover acts imho somewhat more stable than the original cover.