I had a Clifford alarm system installed on my MDX, and it adds auto arming which will automatically lock your trucks doors, when you leave the truck, and set the alarm (which I would always forget to do...)and the doors will lock when you start the truck. It does integrate with the factory alarm system, so you actually have both of them running. You must use the alarm's keyfob to operate it, and not the Acura one (just stick it in a drawer and forget about it) - but that doesn't bother me at all. The main purpose for me installing the alarm system was not for anti-theft, because if "they" want it, "they" are going to get it, it was to all the auto-locking - this is a MUST.
Just my .02