With all due respect this video from Film Riot seems to contradicts what you are saying. In that recorded to the atomos in prores the image has less noise. https://www.youtube.com/watch?v=fSyl2LeSGOA
Ha thanks for the heads up, submitted to the giveaway a few days ago!
Thanks for the responses, and my initial gut instinct as well is to go the C100 route and allocate the money I'd save for other things. However if a distributor wanted to purchase my film do you think it would be worth more to them if filmed in 4k? Also do you think the ability to push the image further in color grading with the GH5's heftier codec and ability to crop and do camera movements in post is worth the extra I'd spend?