Purchasing the Canon EOS-7D Mark II was an absolute disaster. Not only did I lose over a thousand dollars, I wasted numerous unrepeatable opportunities for sports action, of my kids.
There's always another Olympics, a Super Bowl or World Cup. Some sporting icon will do something amazing, and be immortalised by a phenomenal, or lucky, photographer (or maybe it's a phenomenally lucky photog!)
When it comes to your own, there may not be another event, so missing, or messing up is not an option.
I've had great results over the years with my original 7D, and the only things (I found) lacking were the number of focussing points and the continuous shooting speed. High ISO performance was not in my 'field of vision' at this stage, but even so, the Mark II still had it.
The rumours, and the eventual announcement, of the Mark II confirmed that the 7D Mark II was everything I needed in a new camera. Theoretically.
I had tried, considered, and rejected the higher quality of a full-frame DSLR. The 'sportiness' advantage of the 7D outweighed the quality of full-frame.
Except when you can't achieve the focus, reliably...