Actually, there are big differences between agencies. There are major differences even at the OW level. Some agencies are better than others, of course, what constitutes better is opinion. I believe better means a more comprehensive approach, more time in the water and that time spread out over several weeks, others have a different definition. I will agree an excellent instructor can overcome shortcomings of his agency. Unfortunately, excellent instructors are rare. Look farther than the one shop you've found. Dive shops are not the only possibility. Colleges, universities, YMCAs and independent instructors often (not always) teach better classes than are found at dive shops.
Talk to the individual instructors and ask questions. Keep in mind, SDI & PADI are not the only options. NAUI, PDIC, YMCA and many others can be excellent choices.
How do I find an excellent course and how will I know I've found it?
Interview potential instructors. Most people never ask any questions beyond price. As the old saying goes, "You get what you pay for." Excellent instructors will usually have a higher priced class for a number of reasons. The instructor is dedicated toward providing you all the time you need to master necessary knowledge and skills. Extra pool time can be expensive. Keep in mind; the instructor is trying to make a living. His time is valuable.
Consider alternatives. While many instructors teach through dive shops, some of the best are independent instructors or affiliated with colleges, universities or YMCA's.
How long have you been teaching? Most instructors improve over time. They learn new techniques and get ideas from other instructors and through experience to improve their classes.
Do you certify all your students? Only instructors who are in a hurry and care nothing about your safety will answer yes. You want an instructor who will require you to be safe and knowledgeable before issuing a c-card. An excellent instructor might tell you that he is willing to keep working with a student until the student either qualifies or gives up.
What skin diving skills will I learn? While there is some disagreement on this point, many professionals believe a solid foundation in skin diving will not only make you a better SCUBA diver, it will make learning SCUBA easier.
Will I learn confidence-building skills? There are some skills which have no direct application to a typical dive, but which do build your confidence as well as your abilities. This, combined with an understanding of the panic cycle, will make you much less likely to panic.
Do you teach the panic cycle? Panic is the most dangerous aspect of diving. Many instructors do not understand panic and believe there is no way to combat it. In actuality, panic is understood. It is though learning the panic cycle and by increasing skill levels that panic is avoided.
Do your students swim with their hands? This will let you know if the instructor pays attention to details. Good divers do not use their hands for swimming.
Do you work on trim/body position? Divers should be horizontal in the water. Good instructors will see that students are striving towards good trim. Poor instructors often neglect it.
Do you overweight your students? Many instructors overweight students. It is not a good practice.
What method do you use to correctly weight your students? Any answer that does not involve actually getting in the water means you want to avoid that instructor.
Is the instructor patient? While talking with your potential instructor, you should be getting a feel for his personality. Patience is an important quality for an instructor. You want to avoid instructors with a drill sergeant demeanor.
Would I be happier learning from a man or a woman? Only you can answer that question, but in general it is not usually a serious consideration. There are excellent instructors and there are poor instructors. Men and women fall into both groups.
How many people will be in my class? Small classes are better. You'll have more individual attention. Unless the instructor is using assistants, more than four students are difficult to watch.
How many certified assistants will you be using? Unless the class is relatively large (more than 4 students) this should not be an issue. An instructor should have a certified Divemaster or Assistant Instructor for every two students over four. There are times when divers working on their Divemaster or Assistant Instructor certifications assist with a class. This is normal and not an issue, but they do not count toward the assistants an instructor should have when working with larger classes.
Will I be learning skills kneeling on the pool bottom or mid-water? This question is not critical, but will let you know if you've found an instructor who has a great deal on the ball. The over whelming majority of instructors (even good instructors) teach skills kneeling on the bottom. Don't eliminate instructors who do. Some instructors have realized your mask will flood while you are swimming, not when you are sitting on the bottom. You need to learn skills in the manner in which you'll be using them.
...Ask questions. Try to find some information on the shop. There are possibly some dive clubs around your home. Try to get some information. I agree with the one's who said it's all good...have fun because that's diving...a great adventure, always...but if you want to learn more about the shop, these are just a few suggestions...Safe diving and good luck....
