Walter:
What I ment by "cosmetic", is that I cant really figure, acording to training standards alone, which agency is better. I had a look on the list in your site, and personaly, I dont think the difrences between the agencys is big enough to matter too much, so I dont think it's this much of a factor for choosing a course.
You are right about PADI being a marketing organization, but still, the initials stands for "Profesional asociation of scuba instructros", while SSI's stands for "Scuba Schools International".
-->"My opinion here (purely personal) is that an organization of instructors is less likely to keep an eye on it's members, than an organization of dive-centers on it's employees."
Possibly, but OTOH it can place non instructors in a position to call the shots that should be called by the instructor. If you are interested in quality of instruction perhaps a non profit approach might be better for keeping an eye on instructors. <--
In every SSI center, acording to standards, there must be a person that supervises the instructors, and this person is suposed to be an experienced instructor. Where I worked, This function was filled by one of the best instructors I know, and when I did something wrong she was never embaresed to let me know. It helped a lot, aspecialy when I just started. A PADI instructor, on the other hand, can work without affiliation to any center, without anyone to tell him something if he works wrong, and it is easier for him to bend the rules.
"There are differences in instructional philosophies as well"
There certainly are, but you didn't even scratch the surface.
I know I didnt, as it wasn't my intention. I did it in other threads, a while ago.
About PADI instructors and freedom of standards- in certain cases (not in most!) a PADI instructor must work acording to PADI's layout much more than other agencys. This also why in PADI's profesional literature, everything is a lot more detailed than in SSI, where you are given only the highlites, and expected to fill it from you knowledge and experience. PADI's layout even includes time schedules, in minuets, for every part of the course. As for skill, In PADI, not certifing someone becouse he did not pass an exercise tha is not requiered by the system may leave an instructor without liabilty (this was explained to me by a friend, a PADI instructor) and so in other certain cases.
And as for your last remark- I dont think that a none diver will understand good enough the standards and the differences. Ascent rate will mean nothing to a none diver. Of course, consulting with a diving friend is alwais recomended. But still, when you are not familiar with diving, he best thing you can rely on is your common sense.