My former diesel tech is a big fan of the 7.3 gas engine, after working on 6.4's and 6.7's the engine bay probably looks empty to him,though. The worst problem we had with the 6.8 V10 was warped exhaust manifolds and broken manifold bolts, or improperly torqued spark plugs blowing out, the OHC chain drive system gave zero trouble. I like simpler designs better but it's hard to complain about the modular engine family's reliability. 4.6 Crown Vic cruisers took a merciless beating for years. If you haven't driven them, EcoBoost engines aren't like turbo motors from the 80's that needed to be screaming to make any power, they start boosting just above idle, anyone who's towed with both the current 5.0 and a 3.5 EcoBoost will buy the 3.5.