To me, a "PADI 5-star" branding is a potential negative. It means that it's a large operation that is an integral part of the PADI marketing hoopla. If it's a dive resort and I'm staying there, fine. But in a place like Cozumel where there are many excellent small owner-operated dive operations, PADI 5-star might indicate cattle boat.
"might" is a good caveat. Aldora is a 5 Star Instructor Development Dive Resort per the PADI website. They are hardly a cattle boat op. That is only one example.