Currently I'm using Canon 550D with Sigma 17-50mm F2.8. I'm looking for upgrade to FF camera, and from my budget D610 or 6D would be great choice. So I searched reviews about both camera and D610 looks better in terms of image quality. I tried both model in local store, found myself I got easily comfortable on 6D control but not so much on D610, probably because I'm Canon guy right now. So I bring this question here : should I buy Nikon D610 or Canon 6D?