I am looking for some un-biased feedback from tradesmen regarding the most reliable residential split systems available today. This would include gas heat/AC, heat pump, and dual fuel combos. It's been ten+ years since I have been an active installation/service tech. I now work with building automation controls. I still perform service and replacements for family and friends, but have lost touch with knowledge of the current brands/models.
When it comes right down to it, most of the "guts" of any given unit are made by a select few manufacturers (compressors, motors, metering devices etc). The major differences would be in the design and manufacturing of things like the condensing heat exchangers of gas furnaces, the refrigerant coils of the AC/heat pump units, the electronics, and the cabinet itself.
I'd simply like to know which brands have the best track record as of late for reliability and lowest repair costs. Some of the proprietary components can cost more to repair than what one might save in energy during the life of the unit.