I have launched the Orion pocket-rocket flares, and the AF gyro-jets. I prefer the gyrojets, but don't have a source for them, and imagine they cost more than orion's product. The Orion flares, so I am told, are similar in form and function to the flares the Navy uses. They are based on a ballistic charge of medium handgun-type size, fire up, and then burn and fall. The gyrojets are rocket-powered, and burn on their way up, making it easier to pinpoint the launch source, and putting less of a kick in the launchers hand. The gyrojets have a better reliability primarily because they are easier to load and launch. I had no Orions fail, but I did have some I had to try two or three times because of seating problems. The orions also leave a insert in the launcher that must be removed before the next flare can be screwed in. This increases reload time.
Should you participate in an activity that mandates carrying flares, the Orions are the way to go, though. Each individual shell is sealed and labeled with an expiration date, which was a requirement for the state I needed them for. The gyrojets were not labeled with an expiration date, iirc.
Enjoy, and may you never need to launch a flare except to see what it looks like.
Stryver