I did back when it wasn't very expensive. I've run a 100 dry shot on two stock 5.0s. They're a lot of fun, but ultimately I'd rather a power adder that's always there or a motor that makes the power naturally. Many states have laws prohibiting NO2 on the street, and if there is a system failure (slim chance admittedly), you have a higher probability of the failure taking out your engine too.
I always had that "what if" in the back of my head too having that bottle in the car. It's not a flammable gas or anything but if mommy soccer van hits you just right, that bottle can violently fail, sending shrapnel missles everywhere. A regulator knocked off one of those bottles will take your head off.