The first job I had in air conditioning, 30 years ago, was building demonstration trailers for a Carrier dealer. Their version of ductless was a 3 zone system called Multiplex. Once they discovered that I had the fewest leaks at the flare connections as compared to other technicians they had me do all the flares and start ups. I was not impressed with that early Carrier design. When charged correctly the liquid lines would gurgle; the customers would complain and the next technician would overcharge the refrigerant. When a system was too much of a problem the company that I worked for would have us remove it and replace it with a Daikin system and there would be no more problems.
For a while Daikin either quit selling in the USA or at times did things like using a proprietary refrigerant and I decided that I did not want to stock yet another kind of refrigerant in the truck. And for a while Mitsubishi dominated the ductless mini-split market. Integrity Air became a Diamond Dealer after training in Atlanta. Since then we have returned to Daikin for the longer warranty and just recently Daikin started making them in Texas. Most others are made in Asia.
Where do most people choose to use these mini-splits? That has changed over the years. Systems for three or more zones are mostly being used the same as always. These mini splits are wonderful to use where it is difficult to get ducts installed. Another reason homeowners and business owners both are moving to mini-splits is for the amazing energy efficiency. And did I mention quiet? I installed one for my office worker and she says she loves the quietness of it. Single zone use has changed. We used to mostly install them for “florida rooms” … the back porch that was enclosed with windows. Recently more people have used it for a bedroom. If the bedroom got poor cooling from the central system or the customer, as an emply nester with a big house discovered that it is the best way to stay ‘way cool’ and use less electricity. Another couple chose to use their main house as an AirBnb. To accomplish this they had us install a ductless system in the finished garage and stay there when there are guests. We have installed for an art studio and offices as well as office conference rooms, computer or server rooms or where more capacity is needed like a restaurant or church building.