Wow, that is crazy. Kind of changes the dynamic. If one leans towards video this would be a great choice over a mirrorless unless you needed gimbal. But why not get both? Go for a cheaper mirrorless.
I own the C200 which is the little brother of the C300iii let me explain my opinion of those cameras..
The C300iii with S35 manual cine glass and a competent first a/c can make amazing movie quality images I am very sure.
Im very suprised low budget drama/film schools/poor countries are not skipping onto C200 C300
Sadly this is not where my commercial offer sits
1) EF lenses fit almost anything from alexa to sony.
The EF mount on the C200/300 (which procludes the use of a 'speedbooster') and S35 sensor really does not sing if you own fullframe glass.. even if it is EF glass.
My C200 I really only use with my 18-35 stigma 1.8, nothing offeres the DOF zoom range of the 'basic' fullframe 24-70
1a) Canon rf24-105 2.8 and others are exellent lenses that you cannot even rent to put on an ef camera
2) If you want to remote control on a device the cat 5 connectivity on the C200/300 is sht slow, the cameras are not listed on the Canon apps and dont have usb3
(you can buy a complex lanc based canon control box now used for $1000.. but that eats into your C80 budget fast! and has not forward compatibility)
3) Auto focus is poor.. this means that you will need an a/c.. which adds significantly to the day rate (Im assuming I as operator might be doing something complex like using a gimbal or jib - so need an a/c or decent af)
4) 'puch in' to check focus is poor so MF operation is extra stressful unless you add a monitor
The C500ii I operated last week also has a weak punch in so MF was scary.
(The punch in on the r6i is excellent and re-sets your standards)
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Compare this to the FX30 being 'the answer..'
-can use a speedbooster
-usb 3 app connectivity
-24-70 available, 20-70 available
-competent autofocus
-decent puch in
-also $3k -no ND
-600g
