I am beginning to realize that! Hopefully the perceived value I receive from TDI courses will be greater than that of PADI classes. We'll see!
Keep the old adage in mind "It's not the agency, it's the instructor!"
Yes there are some differences between the agencies from a philosophy and course-content standpoint, but "agencies" don't teach classes. Instructors do.
My only TDI course experience was so-so at best.
On the other hand, I did my tec training through PADI/DSAT with a "PADI Instructor" who is phenomenal. Yes he's "PADI" but he's also an accomplished wreck/cave diver with a GUE background and has as rigorous and disciplined an approach to training as anyone you'll likely come across. And he'd have the same approach no matter which agency he was "with."