Kodak film since I began shooting. The colors, grain, ability to push and pull in processing, the sensitivity to slight changes in light....the list goes on and on.
I was lucky enough to test the new Kodak 400 Color film before it came out a few months ago and it is quite an amazing thing. The grain is incredibly fine, so much so that the image really feels digital in terms of clarity, detail and crispness while still allowing for the joy real film provides. It's the first film I've found to integrate the best of both worlds.
Whenever I want to shoot gorgeous fine grain images, this is the film I use.