Stability would be a nice feature

Now how about IPP2 support and tetrahedral interpolation?

So like last year?

Any DSMC2 Red camera (6k Weapon, Raven, Scarlet-W, Epic-W, Helium Weapon, 8k Vista vision Weapon) shoots 2K and 4K scaled prores and DnxHD (except the raven just does 2k prores, not 4k). That being said, I usually still shoot 6-8k r3d because the codec is more efficient and flexible than 4k Prores if going for a 4k finish, 2k prores is fine for lower budget post houses or places that aren't prepared for 4k. I wouldn't recommend cropping in very far since you're basically zooming in on your lenses's imperfections and the sensor's noise patterns. I hate most chromatic aberration personally.

The paid version of RAW Magic converts to DNG and compresses in one pass, and is only $30. See your double post that I replied to earlier.

Shot professionally on a 5D2 and 5D3 Raw.
Workflow: Batch convert all .mlv files through the paid version of "RAWMagic" ($30 - there are free alternatives but from my experience they require two transcodes, one for converting to dng and the other for compressing it lossless, RAWMagic does both automatically). I do suggest converting to 12 bit compressed raw, which is something like 3:1 compression and will cut your file sizes in half for no cost in quality. I don't know how Vegas handles cinema dng, but you can always use davinci resolve like to convert and lightly grade to ProRes or DnxHD before importing.
Is it a hassle? Depends on how you treat it. It's obviously not practical for event shooting like weddings or concerts, the file sizes are too large and card changes too frequent. I found it good for shoots where I had the most control. Keep in mind the media costs (computer hard drives are relatively cheap), I suggest the Sandisk extreme pro 1600x cards. Again there are cheaper alternatives, but they can yield inconsistent speeds and aren't worth the 10-20 bucks of saving (I've had off-brand CF cards downright fail before while transferring footage, luckily not on a professional shoot though). 128gb is a good place to start, get at least two cards so you can dump one while shooting. Treat your workflow like film - be conservative with your takes and try to get it right the first couple times since you will have limited space (128gb ~ 24 minutes for 1080p). The greatest thing about shooting like this for a while is that it trained me to be smart about managing media on sets so that when I started shooting Red Raw the size space or workflow didn't phase me.

Raw is a pleasure to grade, and the sharpness in Raw is night and day on the 5D3, the compression really is that camera's biggest cripple for video.

On a semi-related note. ALWAYS backup your footage to at least two separate hard drives at any given time. Redundancy is not a suggestion, it's a must if you shoot anything digital professionally, Raw or not.