Quality? It might take years of observation if not expert training on RF Sealing of the bladders, stitching methods and nylon material knowledge.
What people think they like is an entirely different query.
With no exceptions that I can think of,
there have been no design or material specification failures in quality among the top manufacturers. Anomalies in the manufacturing process do occur and the few that do are quickly remedied by recall and replacement. They're all right in the same top level quality bracket.
Automobiles should be so good. They are not, not by a longshot.
Here's how the government (god help us) evaluates them by NEDU
http://rubicon-foundation.org:8080/dspace/bitstream/123456789/3558/1/ADA388932.pdf
Anecdotes... is that you want? I have a Cousteau BC that I dive 27 times x 2 weeks a year, then each of those weeks, it gets dried out and stuffed into a big Rubbermaid box, placed in a Honduran shed where the temps likely reach 140° over the summer. Rats have chewed on (so far) unimportant parts of it. It still works. I have no idea how long it's been since they made a Cousteau BC, but it might have been over 20+ years ago. They're on eBay right now going unsold for $20. BTW- the last time they serviced my reg after such storage, a cockroach climbed out of it. This periodic maintenance stuff is a really good idea, I must look into it. But... for now, I blow it up, wait for any leaks, test the purges, and hope that it still fits. The heat makes them shrink in that place around my gut.
Back home in Chicago I collect BC's like kids collect I-Tunes apps. I must have four hanging from the beams and a couple I have never had out of the box. They just seem to appear at the door. Hanging up there's a Mares Stilleto, a DUI with BPW set-up, and a Poseidon with lumbar support, and the other is a standard wrap-around Stab Jacket- I forget what brand. They are all built better than any Japanese car I have ever owned. Equal in quality.
Utility? That's another question entirely, and highly subjective. I select the right BC for the day of diving I am going off to enjoy. Each has it's utility and inherent values. None is perfect for everything.
To give you an understanding of my perspective, I now seem to have 4 dive computers. Me? I prefer wrist mount, I have my reasons, but each of them does more than an Apple 2E with the price tag to boot. I have also learned that under stress (effected by narcosis, the situation, and my feeble older mind) combined with the complicated gyrations needed to operate them, I often wish that I had remembered to take my wife's simple hockey puck computer along as well- with the green-yellow-red pixel thingies.
Again,
personal perceptions of utility and fit are entirely a different matter and by deffinition, quite subjective.