Originally Posted by
airsurfer
The EOS R is smaller and lighter (but not much) than the 6D, due to the lack of a mirror box. Moreover with the (included) EF adapter, you can continue to use all your EF and EF-S glass on the R. The R is more or less a 6DMk3 as it is the same 'entry' level FF DSLR of Canon, but without mirror.
I hadn't seen the reports of the EF adapter being included; interesting -- not that the base adapter is expensive.
The 6D is good enough (right now), and the EOS R not
that much smaller or that much better to be worth the fairly sizeable investment for my particular use. The live view focusing, where the 6D is old enough to be very slow, would probably be the big inducement for some; as might the ability to use EF-S glass (but I don't have any I'd care to reuse) -- but the R with any lens I could see buying is still going to be too bulky to be a grab-and-go camera to replace the M3. If they stick with the system, I imagine there will be a smaller rangefinder style one at some point, and some of the smaller Sony FF rangefinder-style builds indicate that it
may be small enough to get down to basically one camera for everything. We'll see