I used foam to seal a gap between the foundation and the sill plate. Took about 20 cans for roughly 170 lineal feet. Massive change in draftiness.

I decided to use individual csns because they allowed me to work for 10 or 20 minutes at a time and then stop and not have to clean up anything. I looked at the cost of buying cylinders and it wasn't much different given that I might lose some and I'd have to spend more time cleaning up the equipment.