Arri have now released the Alexa Plus 4:3, bringing full frame Anamorphic capture with the ability to record Pro-Res to SxS cards (with an imminent firmware update) as well as Arri Raw (to a codex recorder). This is digital anamorphic shooting come of age; and the convenience of shooting to cards while capturing the full anamorphic image makes this the ultimate camera IMHO and outweighs any perceived advantage with the resolution of the Epic.
Arri had already released the Alexa Studio with a 4:3 sensor and a rotating mirror shutter giving the camera an optical viewfinder. As anyone who shoots with digital cameras knows, electronic viewfinders are a complete pain, and the idea of having an optical viewfinder back is very appealing; however having tested and worked with the camera I find the opposite to be true. The addition of the mirror shutter adds considerable weight to the front of the camera making it heavy and unbalanced. viewfinder flicker now seems annoying, being now used to seeing exactly what you are recording while you are shooting, it seems a step backwards to not having the actual image in-front of your eye, the camera can only display an image in the viewfinder or through a video out…not both. Arri have addressed the other problem of having a very dark image due to a stack of NDs in-front of the lens (common when shooting native 800asa) by building NDs into the camera behind the lens. There are rumours of a vastly improved EVF on the way, and one of these teamed with an Alexa Plus 4:3 has to be the way forward.