The 10-speed shifts buttery smooth IF you run premium fuel. Ford won't tell you that... on regular when it pulls timing there's too much going on. You have minor turbo lag, defueling/timing/dbw throttle reduction during shift, and whatever the trans is doing also (it locks the TC in most gears and unlocks during the shift) - there's a lot happening. I started using premium and the shifts became nearly seamless. There is no cost benefit to the premium, perhaps 0.5mpg improvement but that's about it. BUT, on a 700 mile round trip, still on factory rubber, I averaged 23.5 mpg in a supercab 4x4 with capper, so it's not like I'm dumping premium into a 15mpg vehicle. Granted, this is the "best ever" mileage in it, and it's usually 21.5, so that should be taken as everyday mileage, but it's nonetheless an impressive feat.
For most truck duty where it's unloaded M-F, I think ford scored a win here. Trucks are the luxury cars of today. Even if the naysayers were correct in saying a 2.7 will be overstressed, most of these are commuted around empty.
When I hook the travel trailer up to it, it pulls GREAT and there is no lack of power. The 2.7 has more than enough HP and Torque to get the job done. Those numbers themselves would easily be at home in a 3/4 ton or more.
Reliability. I think the engine is solid, but the complexity will be a factor as they age. There are 2 separate fuel injection systems. There's the turbos and associated cooling and oil lines. Ford has had some nuisance issues with o-rings on the turbo coolant plumbing, which doesn't sound bad until the intake has to come off to pull them out. Some of the 3.5s suffered from timing chain guide wear, and the RV guys often run a grade of oil thicker. Some of the 2.7s suffered from valve seal failures (ford recalled them), and the seals are somehow integrated into the heads, causing full head replacement. This is no different than the pentastar. There's an o-ring for the high-pressure fuel pump (HPFP) that lead to gas in the oil in some of them. I don't think the hard parts will be the issues with these engines. I think the small rubber and plastic bits, multiplied by complexity, will be the aging culprits for these motors. It could almost be a time factor rather than mileage.
It's not an easy engine to work on because of the tall body. the engine is tiny and sits way low in the engine bay. You need a stool to get over the fender and then have to dig deep to get to it. The warranty engine repairs for heads or long blocks were often done with body off rather than pulling the engine up.
In mine I'm suspicious of oil-fuel dilution, as the level seems to have increased a little through the OCI. Knowing this, I'll probably change at 7,500 miles with a 10-30 oil rather than 10,000 on 5-30.