When doing my due diligence and I did a lot of it, I found that in my area with my electric rates 0.076 kw, according to the online calculators the payback period got up into the teen years. Plus in my past experience, higher efficiency means more things to go wrong, one service call wipes out years of savings. So bought the 15 seer Daikin. This is of course the way I read it, you may see it different.
I also noticed in videos that the pro's were installing Mitsubishi, Fujitsu and Daikin. I also found that Daikin uses thicker copper in the coils same as the other two high end machines. The rest use thin copper. With most leaks being in coils it seems like a good thing. I am basically without a warranty so skipped the high dollar units. Warranty's are mostly for parts and do not cover labor so the way I see it better to buy a new unit if one goes belly up.
I have had my three Daikin in for 1 1/2 years, they are too efficient and my humidity runs high, am now experimenting with using dry mode or adding a dehumidifier. I am in high humidity Florida.
The unit in the master bedroom is pointing at the bed, if doing again I would not do it this way as I find the constant breeze annoying.
I got mold in the main unit and it is an absolute PIA to remove the bower wheel to clean. Mini splits get a big fat ZERO for serviceability. Daikin is not the worst from what I see online. The bags and sprayers available online were not working with the mess I had! Google mold on mini bower wheel.
My electric bill for July pre minis would be in the $125 to $150 area, this July it was $86. The minis are used differently so almost an apples to oranges comparison. Office is kept warm, bedroom is kept cool, more control. Use very little heat, but heat pump really shines on energy savings for heat!
And of course only my opinion and worth what you are paying for it.