I actually use neither for cartotanks. I generally just rinse a tank under running water, and if there is any film on the glass after this, I will do an additional rinsing with a Q-Tip applicator. Occassionally, after a particularly stong flavor like cinnamon, I will do a gentle soak in mild soap dish detergent and rinse well.
I've just started using drip atomizers and to clean those I was just soaking them in hot water for less than an hour, blowing them out, and allowing them to totally dry out prior to use. This seems to work fine, however I did by some cheap vodka to try soaking them in to see if the results are different. I've not tried it yet.