2019 GT, manual, 3.55 gear.
Mine is a road car. I run mostly interstates and 2 lane highways out in the country. Very minimal traffic. 75mph on the interstate. Desert Arizona. The average over the last several thousand miles in 27. I do not hotrod it, nor do I hypermile.
I have taken 2000+ mile trips in mine, and I think it is a fabulous road car. Very comfortable and steady as a rock cruising the highways. I say go for it!!!
If you read carefully, you will note that there was a material change from nylon to another type of plastic. I doubt that it was only one lot involved, unless they make 40,000 of them at a time.
I had a similar experience with mine sitting on the lot for 10 months. Replaced the battery and it has been fine ever since. I also did not go with a Motorcraft battery.
Best I have seen on my GT is 31 on a nice, leisurely trip. Mine is a road car, so the overall average after 13k miles is 27.7. I know that is probably a bit high, but I will take it.
I would suggest that 15 minutes is not enough. The oil needs to get good and hot to boil out moisture and stuff, and unless you are running it hard, i doubt that 15 minutes is enough.
If you are going to drag race it, then the A10 is faster. For me, the 6 speed is much preferred. You ALWAYS know what the gear selection is with a manual. Automatics think for themselves and you might not always agree with it.
Digital dash is well worth it. If the car was treated well, 50k miles should not be a problem. It is probably a road car and those are pretty easy miles.