"As an HVAC mechanical engineer, if you tell us you don’t care about a brand it’ll open up an entire industry of options. Almost all packaged equipment has the same efficiency and warranty, but some brands just cost way more than others because of whatever internal proprietary controls they have or inflated egos or whatnot. I can design you a system for 30-50% less sometimes if you give me the flexibility to do so.
I can also show you a comparison to prove to you that two systems of different costs will operate equally."