There are two main model rocket reloadable motor system motor manufacturers. I have mostly flown Aerotech motors. The Aerotech motors are great and also a bit cheaper because the consumer does some of the assembly. Cesaroni Technology Incorporated motors are mostly assembled and they are pretty darn cool. I borrowed one for my Level 1 launch and loved it. Picked up a 2 grain case and some motors. Above is my test Flat Daddy using a Smoky Sam motor. It was a quick and dirty flight.