I understand where your coming from, however hindsight is always 20/20 in regards to photography and camera gear. With the 7D it magnifies so much more due to all the extra MP that any and every little flaw in focus and or lens will be that much more magnified. I had the pleasure a few months ago to run into a CF card with pictures I didn't delete yet which were from my old 30D and sigma tele lens... During the time when I had that camera, it seemed to constantly pop out amazing photos one after another, however looking back at that card and photos, now with my increased expectations, I would be ashamed to show any of those photos on my portfolio due to stuff I may not have noticed during my time using that camera. It doesn't mean the camera was bad, but my increased expectations of me, of my current gear, of my skill set has changed. Comparing different, especially older generations of cameras is apples to oranges due to that same reason. 7D is a beast of a camera, but on the same note, any slight issue will be that much more magnified.
Nail, head, hit.