So, I compared some stuff and wrote a thing:
If you're interested in the objective differences of large format cinematography to regular S35mm images, you might find it worthwhile.
It's a quick test comparing regular S35mm Alexa, matched for both field of view and depth of field against the shiny new Vistavision-sized sensor of the Alexa LF, using spherical lenses.
If you click through to the vimeo link, you can download the full 4.4k ProResHQ file in all its glory, which I'd highly recommend pulling into a piece of grading software to look at up close.
The test certainly helped clarify a few things for me.