3.0L, not a 3-cyl... Its a VM Motori engine, split ownership between FCA and GM. I wouldn't recommend a diesel in a half ton ever, other than if you do a TON of highway miles, or tow moderate loads all the time (in those cases, the diesel has advantages). However, those engines have been around a long time, and are known to be extremely reliable (used in medium duty truck in the EU for well over a decade). I've driven a friends EcoDiesel Ram that has over 250K miles on it (highway of course), no issues with the engine or trans, the whole truck has been almost bulletproof (seized caliper is the lone exception).
Regardless... if you're buying the truck outright, and plan to own it more than 5 years/100,000 miles, at least stick with something naturally aspirated (unless you fit into the diesel group above). Turbo's don't last forever, and the engines they power have more issues than an NA motor typically as well (they have more parts, more parts inherently equal less reliable). They do make great power, and with power, comes thirst. The EcoBoost is great on fuel if you stay out of the boost... If you tow anything, or are hard on the throttle, expect mileage worse than just about anything else.
I've driven Ram trucks quite a while now, and my current truck is a Power Wagon. Not fast, not cushy, not good on fuel, but it hasn't given me any problems in 90k miles, and it goes where I point it (locking axles, disconnecting sway bar, and a winch are factory equipment). Its a beast off-road, but still hauls my 14K lb dump trailer when I need it to, which other off-road trucks can't...
If you plan on leasing, buy anything you like, there's no crappy trucks made anymore in terms of quality.
If you're going to buy it, and trade it in 3-5 years down the road, resale can be a concern, so I suggest going with a higher trimline of whatever you get (they depreciate much less than a work truck package). Limited, King Ranch, Longhorn, Denali, etc... More now to spend, but gives you back just as much or more later...
