So the 5 has 8 stop IBIS.
"Stabilization gets better if you pair the in-body stabilizers with a compatible RF- or EF-mount lens."

So has anyone found the list of EF lenses that it is compatible with?
How would this stack with the in body IS of my 500mm?
This might be a bigger improvement and benefit to eliminate noise in low light than having the lower mp sensor. I can get my 500mm down to 1/250 before shake really becomes an issue. Getting it down even lower would be huge.