I built a Performance Rocketry Little Dog Dual Deploy. I have a little video which describes the rocket on youtube. The first launch was a disaster which resulted in a cato. (cato is rocket dork slang for a CATOstrophic (sic) failure of the rocket motor.)
The 2nd launch was (mostly) a success! I was going to launch with a J motor but because of clouds I used an H motor instead, so a quarter of the total impulse. According to the sim it should have gone about 2000 feet, but it ended up going about 1500 feet.
The rocket wobbled a bit early in the burn. The streamer was supposed to pop at apogee and then the main chute at 700 feet but they both came out shortly after apogee. I think the payload pay just fell out of the booster when the nose cone was blown off. But as failures go, that was a pretty good one, as the rocket descended nice and slow and landed in view.
I was happy with the launch because I loaded 2 motors and they both worked fine. My altimeter worked, too, and fired the deployment charges. My failures were the wobble, which might have been solely because of the slow speed, and the fact that the main deployed too early.