I have two and getting a third - basically I'll have one on each TV in the house.
In our case we rarely game although the young lad (5) enjoys a few racing games and they've saved me buying an xbox for him. In our case it's purely for TV viewing/streaming. Benefits to me:
- Love the UI. I can set up a really simple user interface with minimal clutter. Mine all boot into the restricted profile with only the allowed apps visible. Kids have limited access to content and that does myself and the wife.
- 4K with HDR.
- Plex is fantastic. I'm a complete convert from Kodi. Plex (client in my case) gets special attention on the Nvidia Shield and they work put a lot of effort into new features
- High resolution games on their highest settings
- Support. Nvidia are still supporting the 2015 model with new updates. I doubt most other Android boxes are still getting specific updates
I have an Amazon Fire 4K and much much prefer the Shield. Does everything I need. I even replaced a Dune Solo 4K media player and using a Shield into the projector (130" screen) and it's brilliant.
I'm even thinking now of getting a digital tuner (sat or saorview) and using the Shield/Plex to view live TV. No idea would I actually use it permanently for TV but I'm interested to see what it's like.
I have both the 2015 and 2017 models. I actually prefer the new model. It's more compact and the controller is streets ahead of the older one.