My 3c of personal experience....
I had a 5Dii. Found DPP slow, but also I was moving all my workflow and computing over to Linux. Darktable, Rawstudio - some excellent software alternatives in the Linux world.
Then the 5Dii shutter died .. at under 8,900 clicks. Quote for repair was equal or more than a used one on auction sites. sigh
Went out and bought a 6D as they were on special. For once I got the lowest price since release (its gone up again due to exchange rates).
6D - lovely camera. I actually like using it more than the (heavier) 5Dii.
In-box CD .. coasterware. The previous versions of Canon software were Ok-ish, this was all based and tied to SilverLight, which is banned from my systems since 2006. Even Microsoft are telling people not to use it anymore (2015) and move on.
All the raw processing packages which I tested in Linux came up with an non-removable green tinge for Canon 6D images. I got hold of the devs - all use a common library 'dcraw', which is being worked on. Canon changed the raw format and do not reveal any info (as with printers and scanners), so this has to be reverse engineered for Linux. I have no doubt this will get fixed, but it will then take time to trickle down to the packages and the distros.
So in the meantime .. I shoot carefully on JPeG. :(