I have to agree. There are some guys with them maxed that are happy with them but I personally think 2.1 looks best. I have seen a few set at max that appeared to be nose high. Not to mention, 2.1 will put less stress on your front end components and is less likely to cause vibration, steering, or alignment issues.
Partially depends on what size tires you plan on running too. If you want to run full 35's I think you need them at 2.8".
At 2.8" it will probably sit dead level or slightly nose high so you'll want to add a rear coil spacer as well. They are pretty cheap from Top Gun Customz. But it is another cost....
I have mine set at 2.1 and my front sets up about an 1/2 in the front. Im thinking of getting a 3/4 spacer for the rear, and see how it turns out. I know some guys have theres set at 2.8 and say there truck is level, but im not sure why mine sets like it does at 2.1.