Which is better, Chevrolet or Ford?

Find a great instructor, no matter the agency.  And have way too much
fun.

*

Ahhh, a "Good Old Days" scuba question :-)

Star's already answered the question.  To phrase it another way:

"Its not the Agency, its the Instructor".

My general rule of thumb is to go visit your local diveshops and spend
some time talking with them, to see which ones you're comfortable (or
uncomfortable) with.  

If find an instructor who talks down about the other dive Agencies,
you've probably found someone that you will want to avoid.  

Similarly, if the instructor can talk for 5 minutes about elements of
dive training without mentioning his Agency's name 13 times, you've
probably found a better guy...

FWIW, a really, really old rule of thumb that I had been told was back
before I had gills was that any diveshop that lacked chairs to sit
around in was a shop more interested in selling stuff than helping their
customers & friends enjoy the sport of diving.

-hh