In AZ if you get a black or dark car, I think you are beyond foolish. both of my Mavs have been light colors; and not only are they cooler they don't show the dust.
My 25 Lariat Boost runs just fine in Eco mode. Just returned from a round trip to Taylor AZ (from Mesa AZ), about 320 Miles, high point above 7600 elevation and temps above 105 at lower elevations. I use 91 octane and have plenty of get up and go.
Not seen 93 in AZ, with the heat and my many trips to high elevation locations, I have used top tier 91 year round. I admire the fact that you do most of your own maintenance. At 79, no longer an option for me. Good luck in the coming years.
Starting in the 25's, the Eco engine is almost a total redesign,. Older ones had many problems; suggest you wait a year or two and get a 25. However, many older ones had few problems. So who knows for sure.
Once had Horne Ford said I would have to leave it for 3 or 4 days before they could get to it. So I made an appointment at L H Miller Ford for the next day. I have never been back to Horne Ford