I just bought a Canon 6D, I decided to go with a full frame sensor. I Also considered the 7D mark II and also Nikon D750, as I really like the articulated screen and inbuilt flash.
Here are a couple of good websites showing noise in various situations.
http://www.imaging-resource.com/IMCOMP/COMPS01.HTM
http://www.brendandaveyphotography.com/?page_id=726