I have only flown low power, BP powered rockets. I recently purchased an Estes Scion (evidently a "repurposed" Leviathon, came with 4 fins) and it says in the directions that first flight should be on a F15-4 but that recommended composite motors are F50-6T, G40-7W, G80-7T. After reading on here about adding weight to the nose cone as engine size progresses, I am starting to worry about stability as there is no mention of this in the Estes instructions. I guess my question boils down to if this is something I need to worry about or if these rockets are inherently stabile as long as you are using the "recommended" engines?