Congrats, Stephen. Looks like a pretty good set-up, usability wise.
I bought an IBE HDx35 adapter last summer to be able to use my 2/2" lenses on my F55 and C300 and finally pulled the trigger on a Canon 17-120 in December. Having a real zoom with a useful range makes all the difference in the world with these large sensor cams. The 17-120 still isn't a 13x4.5, but it's the best there is right now in native s35 glass. I did use my 13x4.5 on my C300 for some feature pieces for the Paralympics and I could have never done them without it(not with the shot variety and speed, anyway).
The PL version can have a B4 mount put on it. The Cfast cards a f@#$ing expensive.
The image is fantastic.
The bad: The camera is heavy for its size, good in low light but not great compered to new digital cameras,.. and I still need a ND filter solution... Cfast cards are ridiculously priced, not enough assignable buttons on the outside and it is too reliant on the touchscreen.
The good: Everything else. I LOVE this camera!!!
I read to be careful with the screws for the mounts. Some have ruined the threads from changing the mount. Have you looked into the C-Fast hacks? Seems many have had good luck with it.
I believe you also need an IR filter. I guess screw on ND's are you best bet if you don't go with a matte box. But if you do have square filter, take a look at the Wooden Camera lightweight rubber shade that takes a filter. About $100 bucks.
how does it behave in eng situations. I have only run into them in in house production environments where everything is fairly controlled. So I don't really know is it weather sealed where the parts join? And can you assign enough of the standard functions to switches/buttons?
Not sure about the weather sealing, I've read that its fine in damp/light rain conditions but I don't want to risk it, and that would be a no to the assigning enough buttons, but they seem to improve every software update.