The past IQ of the original 7D doesn't mean the 7D II will have the same problems. For Canon to succeed with the 7D line, the 7D II MUST have better IQ and overall performance than the 70D. It would just be a flop if it did not. If the 7D II does end up being a superior performer to the 70D...would you still adhere to the above statement? (Just curious...personally I find it odd when one single bad experience with one single product permanently taints a person's opinion of something...to me, every product generation is a chance for a new start, a chance for a company to reinvent itself, reinvigorate itself, or if necessary redeem itself (not that Canon needs redeeming, but they do need some reinvigoration in some areas.))
I battled a 7D for three years and it was never repaired properly. The customer service on top of it was the worst I've experienced. On the first day of using the camera, it misfocused badly at telephoto. I should have just returned it, but instead I decided to let Canon do the right thing. Big mistake. I really wasted a ton of time on the issue.
I've never had a problem with a Canon body before that, or with the two bodies I bought after. I have no interest in pursuing a 7DII at all, because the 70D is stunning, and I already have a full frame to go with it.
The Mark IV and 7D, IMHO, focused poorly with certain telephotos, and shared the AI Servo II algorithms and AF CF settings.
Sure, the 7DII could use different algorithms, but I'm just staying away. Bad karma. I came pretty close to defecting over the 7D issue.
If you need an upgrade over the 7D, get the 70D. Why? Better sharpness at RAW (I'd say 30-45%), better color at RAW, much more reliable focus and almost as fast. I had both cameras side by side for a month.