I have one in mine, I did not install it, I have a friend who professionally sells & installs these out of his Audio shop & what he briefly explained to me is that in the PATS system there are 4 available slots for keys that are capable to start the truck, the remote system is programmed like a key & takes up one of the slots in the pats system, His reason for explaining it this way was if I needed 4 people to have keys to my truck someone was not going to be happy, as after the install I would only have 3 keys available, as he was using one of the slots for the remote start module.
Sorry I dont know much more about it than that, maybe someone else has more info.
By the way my remote starter works great & have never had any problems with it, it's an Omega brand, one of the higher end models, he has sold & installed thousands over the past 10 years with very few problems.
JP02XLT