3. 6D is a bit smaller than 7D in my hand. It doesn't have the solid feel like 5D II, III, 7D etc...I feel like FF sensor in Rebel chassis.
It's small yes, but it's hardly a Rebel chassis. The Rebel is all plastic, and not very good plastic at that. It's somewhere between the 60D and 5D3/7D in build quality. I'm quite sure it'll take more abuse than a Rebel or 60D, if not as much as a 5D3/7D.
+1. And being small and light isn't always a bad thing. It's entirely dependent on the user preference. 6D being small and light has its merits. Just asked those photogs that are tasked to carry their camera from morning till night. Even a slight weight difference feels like heaven. I had a lot of times where I shoot at least 3-4 hours straight (with 2 ultra-light lens, 28mm and 55-250 + external flash). Although I find the IQ of a gripped 500D sometimes lacking, it's heaven compared to an un-gripped 5D2 that I was able to carry and shoot once for 3 hours (wedding + reception) (with a 24-70mm lens + flash).
-1 Rebel, xD and 5D,.....to me the weight of these cameras are not much different - in ounces? The lenses...yes. To have a snug fit camera in the hands is HUGE bonus.
Have you ever mount 70-200 on rebel Vs 7D or 5D?
Yes actually and they felt different. If
all else equal, I'll take a gripped rebel. Sadly, I also take IQ into consideration.
I guess you've got a large hand? As I've said, this is purely subjective. That's why I did not generalize. Again, it is entirely dependent on the user's preference.
Of course, I'll still prefer 5D3 even with the added weight more than the 6D and a little bit of loss in IQ (almost non-noticeable) if I got the money.
But with restrained budget, a 6D + lens is more appealing than a 5D3.