The great focusing controversies are layered. AF v MF is huge, obviously. AF marked the end of the romantic era. Like when fighter aircraft moved to AA missiles, with increasingly advanced guidance systems.
Next we have RF vs SLR vs EVF. Since prisms don't apply in the current context (A7r aka Leica Killer) Let's call it RF vs EVF.
I can hear the blood pressure going way up already 🙂
It's only in the last 2 years this could be a serious comparison, and if you have not looked through a nex EVF or an OM-D EVF, you really have no idea on the current level of EVFs.
For a monster corp making everything, Sony has gone to pretty big pains to make manual focus on the Nex system fast and accurate.
The EVFs are super sharp, show DOF as it will appear in the image, magnify to any area of the image, and offer nine flavors of focus peaking.
RFs I think are way cool (i own three) but I'm used to Nex, and can focus just as fast with them.
But no way to overestimate the RF nostalgia here. Its a badge of honor, and loyalty is very very high.
The view through glass is organic, while view into TV is electronic, no way around it.
Let's forget about Sony and Leica for a sec. You have a choice between two cameras. They will use the same lens. Camera A has a rangefinder good as any today. Camera B has a very very good EVF, which with practice can focus as fast. Camera B image quality is 10% better.
Which do you want?
If your answer is A, what % superior image quality would it take to make you choose B?