This might not be a straight forward answer, but what are the rest of your lighting / driving plans? If you plan on adding more light in the future, you will want something to compliment your entire package.
I would look more at beam pattern, over Lumens, below is a bit of why. But Lumens are the measurement of light at the source, so how bright is the light while you are looking at it. What is usually not always available, and my preferred way of measuring light, is candela or Lux. This is the measurement of light on an object, or how far and how well the light reflects to your eyes at a given distance. You can have better LUX / Candela ratings on a light with less Lumens. It has to do with reflector design and other factors. If you compare HIDs to most LEDs, you will see what I am talking about. Take a read at the KC response in this thread.
http://www.fordraptorforum.com/f211/does-size-matter-29703/
If you are considering a "spot" beam pattern later ie HIDs, I would go for a driving pattern beam. If you do not have plans for long range light, for example another LED bar on the bumper, you will be better off with a spot beam pattern.
A driving pattern will give you very good distance, but it will also flood more of the ground in front of the truck, so combining this with a spot pattern, like an HID or other LED bar, you will be able to fill in the "hole" between where the spot pattern reflects light and the truck.
If you are not really considering more light, the spot pattern will give you great distance, still light up / flood the ground in front of you.
To tune your lighting for specific types of driving habits and terrain, you will want to consider multiple lighting technologies and patterns to fill in the "holes" BUT for mostly on the road and gravel / dirt roads, you really can't go wrong with either, IMO.
Did this help at all, or just confuse you more. If you have more questions... feel free to PM me and we can talk over the phone.