As a rule of thumb, I always try to achieve the image and look I want on set, and improve it on post. As many of the previous comments says, ND filters are many times mandatory when shooting on exteriors when you can't control some of the lighting. And regarding color lighting, it's always better to have them on the set, the objects reflects the light in many different ways, and on post this doesn't always works right.
Hi everyone, I don't own any of those cameras, neither I've used them, but I've made a lot of research regarding the Black Magic cameras.
It's up to your taste and to what you are going to use it. The Black Magic cameras are not for live events, like weddings, sports, plays, etc.
In my opinion the BMCs are for film/shortfilm cinematography, were you will record sound on a separate system, you will have control over lighting, you will plan and frame your shots, and so on. Also if you have a laptop with thunderbolt (like the MacBooks) you can use UltraScope (included with the camera) on set for correctly expose the image with the waveform monitor, that's priceless.
By the way, you can record 1080p ProRes, so the storage issue is only present when you shot 4K RAW, which makes sense, you are recording an insane chunk of data.
And the "expensive" SSD is not entirely true, for example a 64GB SDXC is $75, and a 240GB SSD (from the same manufacturer) is $145, which give us a $1.17/GB for SDXC, and $0.60/GB for SSD... so SSD are almost half the price per GigaByte compared to SDXC.
Regarding post production, yes you will need a beast... if you want to grade 4K RAW with Resolve. But if you've recorded 1080p then you don't need such a powerhouse.
In summary, my inexperienced consideration, the BMCs are good if you can also invest in new storage media, rig, battery, external sound recording, and you have control over the shots (e.g.: not live events!). If so, the results will be amazing.
Resolve (it's full version) is included with the Cinema Camera and the Production Camera.
Also is included UltraScope, which is an amazing tool for correctly exposing the image.