You are partially right. I had two 7D Mark II. They could shoot twice the frames which half would be out of focus. So usable frames were about equal. You didn't have an infinite number of JPEGS, no computer could store that many. The 7D II was a Cheaper camera than the 5Ds R. Notice the word Cheaper rather than Less Expensive or Better Value.
As well when properly framed the 5Ds R had twice as many pixels on target and a great resolution advantage.
There's no more pixels on target with a FF 50MP sensor than a 20 MP APS-C camera. As we've both already agreed
, the 7D Mark II has slightly higher pixel density (4.09µm vs. 4.14µm) than the 5Ds. With the same lens the "reach" is practically identical. The 5Ds just gave you more of the scene surrounding the subject. In "reach limited" situations, that additional 61% is almost always superfluous.
As for AF, if you could only get half your frames with the 7D Mark II in focus you were doing it wrong. In his opening paragraph about a 7D Mark II teardown
in which he planned to "debunk" Canon's claims about the 7D Mark II's weather resistance Roger Cicala said two things. He first said, "OK, I have to admit I really like the Canon 7D Mark II
. I didn’t want to because it wasn’t what I wanted." But he then went on to admit, "But despite wanting to hate the 22-megapixel APS-C camera, after a fairly short exposure to the autofocus system, I have to admit I like it. There’s just something about getting every shot in focus every time that’s appealing to me."
In the next paragraph of the same blog entry, he also admitted, "So when I read the claim “4 times more weather sealing” my inner cynic just thought 4 times zero equals zero. But I wanted to be fair so I decided I’d open up the 7D II before I wrote a scathing article about making ridiculous weather sealing claims. Which results in me once again writing an article where I have to admit my assumptions were
less correct than I would have liked. (Sorry, I forgot for a moment this was the internet where no one ever says “I was wrong.”)"
My experience with the 7D Mark II is similar. I have a 95% plus hit ratio when I do what I'm supposed to do to tell the camera what I want it to focus on. It's also never had any trouble in wet weather, either. If the rain gets too intense I do break out the cheap plastic OP/TECH covers, but am still able to shoot in conditions like this:
and get images like this from 65 yards away behind the far end line: