Mitsubishi and Daikin are leaders in the high end of the market, which mainly sell to high income countries, which already are fairly saturated. But if I were making a long bet on the growth of air conditioners in response to global warming, it would be in the markets where there is a lot of growth potential. In these markets, I bet lower priced competitors will have an advantage, like https://en.wikipedia.org/wiki/Gree_Electric