Since buying my 7D I've been unable to use photoshop's CR2 processing because CS3 doesn't support the 7D. And so I mostly use DPP.
However before with my 350D and now when I use my wife's computer with PS Elements 8, I use photoshop and find it's controls on RAW files provide me better results. I think it comes down to what particular controls suit you and how you use them, what yo get used to using, etc. I started using PS's originally and still prefer them. I find I can more easily achieve the outcome I'm wanting with my images in the PS CR2 handler.
