>particularly when it comes to mirroring a tab with a video playing.
That has nothing to do with the processing power of the Chromecast and everything to do with the casting system. It's all just a video stream to the Chromecast.
True, but I wouldn't have had to resort to tab mirroring if Chromecast supported Amazon Prime Video.
Which, admittedly, is also not a Chromecast issue per se, but since the Fire TV stick does support it (for obvious reasons), and since I ought to be watching videos and justifying my Prime membership, it'll probably end up being the more useful product to me. An Intel stick would probably end up being even more useful, since I wouldn't be at the mercy of Amazon to provide support for things (and would instead be at the mercy of XBMC or Kodi or whatever the hell it's called now to provide support for things).
That has nothing to do with the processing power of the Chromecast and everything to do with the casting system. It's all just a video stream to the Chromecast.