IMHO, I'd use the phone.
ASA100 film is the way to go, but you aren't going to have the good, fresh, made in Rochester, Kodak film that you did 25 years ago. Chances are you are going to have to buy some Fuji crap that's been sitting around. Then you don't have the processing quality that you used to too.
Your phone is 16 megapixal and nothing to sneeze at. If all was perfect, the film would edge it out... Maybe... It's not a perfect world though. Since you are asking what film to use, I assume you don't have a lot of experience with the Cannon. Getting the quality with film involves really knowing what you are doing.
The phone... First, you can take 400 pictures if you want and immediately see the results of how things are staged etc. Lighting, composition, angle etc. can all be figured out on the spot. Quality is going to be right up there with the film and it's easier to crop or manipulate after the fact.
My wife has done some professional photography... She left her film camera behind a long time ago... and her high dollar digital stays in the bag 99.9% of the time now.. She pulls out her cell phone most of the time.