I leave mine on (it keeps me outta Trouble), unless I need to accelerate out of a situation, then I disengage it, cuz if the tires break loose (and they will), the VDC shuts me down, then, I'm in trouble!!
I havent had a chance to really test the Armada since im going through the break-in period. I did just hit 999 miles so im almost there. Do you guys leave the shifter in 4 when driving around town? I read somewhere that some people are doing this to keep the engine from searching for gears when in D on city streets.