When going to an occasion the place my main lens was the 70-200/2.8, it was nice to have the ability to drop the EF 40/2.8 into my pocket and swap on a standard focal size lens as wanted (I usually carry with a BR strap hooked up to the lens foot, so the 70-200 may merely dangle from that as I shot with the 40 mm pancake) – it was an ideal, transportable answer.
That’s probably not an possibility with my R3, as a result of having to hold each the adapter and the pancake lens defeats the aim. I’d undoubtedly like a standard or huge (not ultrawide) pancake prime for RF full body.