First gen 3.5, plenty of power. Plan on a throttle body, water pump (some don't have issues), intake valve cleaning, rear shocks, and spark plugs in the first 60-80k miles. Some people add a catch can, some drill a weep hole in the intercooler. I did a weep hole, haven't done a catch can yet.
6R80 transmission: Bulletproof, I've had 5 of them, currently still have 3, zero issues on any of them.
I have a 2017 limited 4wd with the hd tow package, I pull a 4,000lbs enclosed trailer with it across Kansas regularly. It has electronic steering assist instead of hydraulic, so Ford got creative with it. It has a stability control programmed in, think of a side wind and having to turn the steering wheel into the wind, the software does it for you. It also has a towing stability program, it works but adds a weird feeling feedback into the steering wheel. I got used to it after several hundred miles, but the first time you tow with it, it feels weird. The hd tow package includes the auxiliary trans cooler, while towing it stays at 203°, without the trailer it's at 195°ish. I like that you can monitor it from the dash.
Currently I've got 42,000 miles on my 17 and tires and rear turn signal bulbs are all I've had to replace. On the last oil change I noticed the rear shocks have started leaking, so I ordered some replacements but haven't installed them yet. I've been impressed with the brake pad life, but I use tow haul mode and engine braking as much as possible.
Things that could be better:
Heavier hood, this thin one flexes a lot when big trucks go by and I don't like seeing it.
Third row side window seals, they leak air sometimes when the blower is turned up, I have to open them and then close. High powered car washes will leak a little water down them, not enough to puddle, but you have to wipe the inside to get the runs off the glass.
20 inch rims are dumb on an SUV, they should be 17's.
Lug nuts suck, I had a flat and discount tire fubared the nuts on that wheel. I'll probably put solid metal ones on next tire rotation.
Fuel mileage:
15mpg average, highway is 17-18, towing the enclosed trailer is 8-10mpg at 70mph.