I have a slider, but I never use it. The bigger reason I got it was because I thought the tinted glass would be nice (and it is, but not really at night). At that time, the one piece windows were not tinted. I don't think they are now either, unless you get the defroster on the newer trucks.
I put in an order for a Laramie. The rear tinted windo with no slider and defrost was cheaper then the slider, but the slider is powered. I choose the slider! In a quad cab, I can see a power slider being nice.