Quote Originally Posted by Loose Gravel
And you know exactly how much film is left.
The non-pro Canon's often have this too. My EOS 300X does and I find it super handy when using bulk loaded film. No matter how exacting I am I can never get exactly 35 usable exposures in a roll. It always varies slightly.

My Watson loaders also expose the last frame or two when loading the cannister. With my EOS 300X the whole roll is loaded so I know exactly how many frames I have. I can then take 2 blank exposures to make sure I'm on good film. Can't do that with other camera..