The Scarlet is up to user preference. For a 4k file at 14 grand or especially 8 grand it's a deal.
I like my R1's better, but that's me, though everyone in our studio likes the Scarlet more, so once again . . . personal preference.
Compared to the Sony and the Canon C300 the Scarlet is military grade in build and of course it's slightly heavy. Not oh my god I can't lift it heavy, but it's not a FS sony, which is good and bad.
Dislikes on the Scarlet is that damn glossy screen, the menu system kind of bugs me, the sound input jacks need a separate box so you can go from xlr to those mini things. Red makes one for the back of the camera for a gajillion dollars or there are third party.
The file on the Scarlet is very moveable and if you've been shooting any camera with prorezz or avchd you'll be amazed at how much DR you can pull out of a Red file.
Youl'll need some v mount batteries and a belt clip (or you can cage mount). The small battery in the handle only lasts a few minutes.
Personally, I'd buy a R1 because I think it's more robust, but the Scarlet can be hand held and with a Canon IS zoom you can get a smoother walk around image. Not steady cam, but not jerky cam either.
I'm probably going to change our mount to Nikon because I love those little ZF Zeiss lenses and are easy to manual focus on the fly even pulling focus yourself.
I wouldn't do PL for this camera, because why have a 5 pound camera with a 8 lb lens, unless you want to go really good and get a $22,000 optimo 2.2 zoom.
As far as the raw workflow, that one I don't see any negative (pun intended). Cine-x is stable and processes semi fast on a fast computer, but with a RED rocket you can process out almost or as fast as just un wrapping a avchd file and a lot faster than converting any Canon file to pro rezz.
If you edit in Premier you can use the Raw file as a proxy, though it slows up the system, or if you grade out in Di-Vinci it uses the RED rocket and is also fast.
In regards to shooting only 3k, there is no reason unless you want faster frame rates, because it crops the sensor.
Bottom line, IMO is compared to the Canon's and Sony's the Scarlet is serious business and unless you just have to have 5k or a faster frame rate there is no reason to buy an Epic.
Bottom line 2 is with Red Gamma 3 the Scarlet is a full stop faster higher ISO's than the R1's and smoother. I don't know what the Dragon sensor will offer, but the X sensor if fast enough and in the scarlet baby butt smooth.
Bottom line 3 is RED is a serious movie camera company and nothing is cheap compared to still cameras, but compared to the 98% of real movie making equipment, RED is dirt cheap.