While there is a great deal of difference in standards from one agency to another, I doubt you'll find much difference between these two except for the fact PADI teaches tables and SDI doesn't. Neither is known for particularly high standards. Both of them (and many others) are recognized world wide, that's a non-issue.
Why do you feel they are "very competent?" Most aren't. Finding a competent SCUBA instructor can be quite a task.
Are you sure those are the only options? Have you looking into classes away from dive shops?
Take your time to research and find the best instructor in your area. Next, take time to complete the course. A good course will last several weeks. Don't rush this, it's something you can spend the rest of your life enjoying. Keep in mind there are excellent instructors in all agencies. An excellent instructor in an agency with low standards can teach a class that is better than one you would receive from a poor instructor in an agency with higher standards. It will be rare, but it happens. I would suggest asking a few questions of the instructors you might consider hiring.
How do I find an above average 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.
Questions to ask the instructors:
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? Divers should usually 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.
How many people will be in my class? Small classes are better. You'll have more individual attention. Unless the instructor is using certified 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.
Do you dive for fun or just when you are teaching? Instructors who've stopped diving for fun are burned out.
Questions to ask yourself:
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.
- I'm laughing. "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.?
