If you do use the Canon utility to to convert to RAW, then be sure to convert to tiff.
I am not at all sure of the workflow in this case. But I assume that once converted to tiff, then working with the tiff in Photoshop will be roughly the same as what I am doing now. I use the Adobe RAW plugin with PS 7.1 With this set up you first get to use the plugin to manipuale the RAW info directly as the file is being imported into PS. The controls that the plug in offer are similar to those that the Canon software gives you (the ability to adjust exposure, shadow detail, white balance etc.
But once you actually import into PS you are working with another file type,. (you never actually change the RAW file,. )
So by using the Canon raw utility you should get similar results (maybe identical?) but it won't be quite as seemless as you will need the extra step of tweeking in the Canon software saving as tiff and than reopening in PS.
On the other hand, and some have pointed out, you may not need to do any further tweeking after converting the raw. (I find I do most of the time though)
In truth I am just stumbling through all this myself... learning as I go and only recently have I started to get the results I want. (partly due to new optics which demand better file work to do the images justice)
The true RAW masters are Pekka (who works with Capture one) Roger Cavanagh @ http://www.rogercavanagh.com/
and other geniuses like Fred Miranda Check out there workflow. And of course search these forums, there are many who have posted info and help on it here,. and they are who I have been learning from.
These RAW workflows look very daunting at first (it delayed my starting for some time) but once you get it down it is in fact much faster (with the right tools) as the RAW images take manipulation MUCH better than the jpegs.
More good news though is this,. If I am getting better results using RAW than you will too,. as I am a total newbie. Period.