Just recently, I wrote an article reflecting on my use of the Sony RX1 over the course of 2013. I mentioned in that article that I did not own the EVF for the RX1, and wasn't sure that I could really justify purchasing it. In response to that statement, a friend lent me his EVF (which he uses on an RX100 mkII) to try out for a week or so. Here are my impressions & conclusions...
My first impression of the FDA-EV1MK was good. It comes in a very nice, magnetically latched case. It also comes with a smaller eye cup if that's your preference.
Upon closer inspection, the EVF itself appears to be well made of high quality plastic. The hinge has zero play in it, and the swiveling action is dampened just enough to prevent it from flopping around. However, it does not look or feel of the same caliber as the RX1. What that said, it would have been ridiculous of Sony to make this EVF of higher quality materials, as it surely would have raised the price even more!
Technology & Performance
My experience using EVFs on cameras is rather limited. The last camera I used extensively that had an EVF was the Sony SLT-A65, which I believe uses the same technology as the FDA-EV1MK. Prior to that, I've primarily used cameras with optical viewfinders, or no viewfinder at all.
The viewing experience through the FDA-EV1MK is excellent & the resolution is fantastic. With 2,359,000 pixels, it has more resolution than the LCD on the back of the RX1, which has 1,229,000 pixels. Even with the higher resolution, the experience of using the EVF vs the rear LCD didn't offer any advantages in clarity for me. Maybe it's because you're viewing the display inside the EVF at a much shorter distance than the rear LCD? Both of these displays are excellent. It's hard to complain about either! The refresh rate of the FDA-EV1MK is also excellent.
All in all, at no time during my use of the EVF did I feel the need for an optical viewfinder instead.
Unfortunately, for my use, the EVF is just not a practical solution. I don't trust the connection between the EVF & the camera enough to leave the EVF attached in my bag. I also don't trust it enough to leave it connected with the camera slung around my shoulder, or to put it inside my jacket pocket (which it doesn't fit in anyway with the EVF attached).
For me, the decision to get the EVF for my RX1 is less about the performance & specifics of the FDA-EV1MK, and more about using a viewfinder to compose shots in general. I've used everything from full-frame DSLRs to iPhones, and I just don't consider having a viewfinder a necessity anymore. In fact, I feel more comfortable using the RX1 without an EVF!
The FDA-EV1MK is a beloved addition to the RX1 by many RX1 photographers. Just not this one!