Has anyone used DxO Optics Pro 7 with 5D Mk III RAW files and if so, how does the resulting image quality compare with other RAW processors e.g. DPP, LR, ACR, Capture 1 etc?
Pros and cons?
All are good, it depends on what you want to do.
They do not all do the same things.
LR is designed as a complete suite of tooks for photographers, and manages, converts raws, prints, creates photobooks, edits, and a whole lot more. DXO converts images automatically, but does not pretend to be a complete solution.
ACR is a photoshop plugin, so you must have photoshop to use it. Photoshop does not manage your images, which means you will be without a powerful tool unless you purchase management software.
DPP is more of a raw converter, as opposed to editing and all the other things a photographer needs to do.
I'd recommend trying each out, If it does what you need, fine, but if you still have to buy additional software to do what you need, you will want to know that up front.