Experience shows that 100 rounds fired each month in a structured setting will provide enhanced performance more efficiently than 500 rounds fired in unstructured settings. Ask if the institution provides opportunities for post-training practice opportunities. The progression of training should be arithmetic in the increasing complexity of skill development. For instance, you would want to avoid a school that provides a basic tactical handgun course and at the next level has you rolling out of vehicles in counter-ambush drills. Normally, a course should have a dedicated primary instructor.
Nothing is more confusing to beginning students than being bounced around between instructors.
No two instructors, even in the same organization, will teach the same material the same way. As your training progresses, it is a good idea to be exposed to different instructors and teaching methodologies, but at the beginning, student comfort is far better served by instructional continuity. I urge my students and staff to attend courses given by other instructors. But, I do not recommend doing so until a student has mastered fundamentals. There is no Holy Grail of firearm instruction.