Mike Curtis from HD For Indies, has a good take on the C300 with good and bad. It looks like the Camera is aimed at the Sony F3, and not the red one.
It has some better features, but some not as good.
As I said elsewhere, why can the less expensive scarlet autofocus with Canon EF lenses, but the Canon cannot. It also cannot do 444 out, like the Sony can (with an expensive upgrade) which would bypass the Long GOP MPEG 2 compression, making the Sony seem the better choice, especially with it’s higher frame rate (1080p60 vs 24) and 444 capabilities (even if both are after a firmware upgrade to the F3.
Personally I think Canon screwed the pooch a bit, as they missed the price point. At under $10,000 this would be huge, but at $16-20,000 it is too expensive, without enough high end features. And for film it seems that the Scarlet would be better, though of course it does have a much harder workflow.