Many of the new fliers just coming into rocketry may not know, that Doug Pratt of PRATT Hobbies has been hosting a Hybrid Rocket Motor yahoo group now for many years. If you really want the answers to your questions on hybrid rocket power, then join the yahoo group. There are many knowledgeable fliers in the group that can accurately answer all of your questions, and there are hybrid rocket motor manufacturers that can update you on their product lines. This group has photos, videoss & spreadhseets, etc etc that are all devoted to hybrid rocket motor technology. Here is the link to start learning about hybrids again, or for the first time:
https://groups.yahoo.com/group/hybridrocketmotors/
https://groups.yahoo.com/group/hybridrocketmotors/