I’m left-eyed as well, which makes guns a challenge. I shoot with both eyes open and use scopes with unlimited eye relief.
The nice thing about the EX-3 is 1) you can take the eyepiece off with the flip of a switch, and 2) you can adjust the whole viewfinder out to the left. It has a little lever underneath the microphone. This allows the whole viewfinder/LCD assembly to slide to the left a couple of inches, which makes it acceptable to me for shooting with my left eye.
The rubber piece doesn’t rotate, something I think our Canons did, but I just flip the edge back and it works just fine.
We have an EX-1 and an EX-3 and I use the “big” camera the most when I have to shoot (I’m not our primary guy). I like the ergonomics but I don’t hold it like a full sized shoulder cam very often. Your mileage may vary.
Bottom line in my humble opinion, an this is why we bought an EX-3 instead of second EX-1 is that the eyecup and the BNC connectors for monitoring were a significant enough feature to warrant its purchase. I don’t know what the EX-1R has for monitor out, but that stupid little A/V cable used on the EX-1 (if you don’t have an SDI monitor) should get somebody at Sony fired.
Cf