Moose wrote:
"I have already invested enough on long EF lenses (from 200-600mm). But then, I may be able to use an adapter (have to do some research on this subject)."
The EF lenses will work as well as using their native mounts, and may actually work BETTER on the R-series with the EF/RF adapter, than they do on native EF mount cameras.
If you get the control ring adapter, it gives you "one more point of control" when using EF lenses than you would have "native".
There's also an EF/RF adapter with a "drop in" filter housing, but it's more $$$.