The DSLR form factor is pretty much better in EVERYWAY for shooting video than the traditional video camera body. To it's credit, the c300 does get a bit of inspiration from DSLRs, more so than the Scarlet.
Great article here on the Scarlet and some pretty ugly truths about the camerahttp://philipbloom.net/2011/11/20/scarlet/
I've worked on a number of projects involving the RED over the last few years, and the workflow sucks really, really bad. Everything is forever in Beta and there is always a decent chance of something breaking.
The thing about the Scarlet is that it is truly a 24fps camera only. You think the c300 with it's 720p 60 fps sucks?
Well, the Scarlet does 1080p 60fps at 2k, but with the HUGE penalty of being a 3.24x crop. That essentially makes it useless unless you want everything super zoomed or are filming Lions in Kenya. RED is really strange in that the different frame rates and resolution sizes all have different crops, and the 4k 24fps is the ONLY mode with a decent 1.6x crop factor. All the other resolutions have useless crop factors ranging from somewhat passable 2x to utterly useless 6.4x crop.
Any crop more than the 1.6x of the aps-c is undesirable IMO. That's why I cannot get myself to go the GH2 2x crop route (along with crappy Panasonic colors).
Canon will hopefully release a digic 5 Rebel in February to hold us off until the DSLR hybrid comes out. That's going to be the camera to beat.
But yeah, the c300 is still overpriced.