With all due respect, this is a pretty silly argument. As you can see, there are
opinions all over the spectrum for which manufacturer is 'the best thing since sliced bread', and which would be described by others as pure junk.
In my career, I have pretty much specified Carrier, which in many cases was my "go to" vendor because of a couple of reasons:
The rep came often to my office.
The rep returned phone calls.
And most importantly, Carrier also makes a smaller soft cover catalog for the most specified equipment I could keep close at hand, meaning I wouldn't have to wrestle a large binder off the library shelf.
Yep, the catalog being more handy probably resulted in more Carrier sales than say, Trane.
Now that being said, the big three, Carrier, Trane and York, have all been used successfully and they also all have niches where they may have a small advantage over the other. York, for example, has large steam-fired chillers that the others can't match.
Do brands like Goodman call on engineering offices? Not in my experience. Does that make them better or worse than the big three? Hard to say. It does mean that they are not as likely to be specified and/or approved for many projects.
In many geographical areas, one manufacturer may have an advantage, generally based on the efforts of the local sales group. When I was in Denver in the '80's, Trane had a huge percentage of the work primarily due to the reps bustin' their butts to get the sales. This had nothing to do with the quality of the equipment compared to their competitors. It was simply good salesmanship.
Now rickairmedic has had a good relationship with Goodman and recommends that manufacturer. I think that is just fine. He likely has a good rapport with his distributor, he has had an extended period installing and servicing this particular brand, and no doubt would make most any home owner happy with his service. This is probably as good a reason to select a potential HVAC bidder as any. Danski0224 likely has the same type of story to tell.
But what about quality concerns for potential buyers? How can you tell if one brand is better than another? It's not at all easy.
Reading the sales propaganda, it's easy to cherry pick some particular feature or benefit and use that to their advantage. It frequently does little to inform the consumer in any meaningful way. Looking at the units from the outside certainly won't help, and even opening up the equipment doesn't always provide much additional insight.
The truth of the matter is that most of these various brands, both the large national players and the smaller regional ones, are primarily either assemblers of components made by others (compressors from Copeland, coils from Coil Company, fans from whomever, etc.) and only make the sheet metal and wiring harnesses in-house, or are re-branding equipment made by others to round out their product offerings. This has been mentioned in the posts above. As to who actually makes what, I have given up trying to figure it out!
More than any other factor, I would put my faith in the particular installer, get any promises in writing, and hope for the best. That may not be the most comforting thought, but there simply are no sure things in life and HVAC is no different. Regardless of brand of equipment, the installer is your first concern and that is where you should do your research and due diligence. Get an established, reputable, and well respected firm
first, and only then look at prices.
And if possible, buy American
As always, offered only as opinion