All alarm companies have expanders. Just like you said all they do is add more output channels to you alarm and work great. But how many channels does your alarm have now? If you want to add power windows up and down you just have to have two more channels. One channel to roll the windows up when you arm the car and one to roll them down from the remote. I really don't think that you want them to roll down when you disarm the car, it really sucks when it's raining outside or is just flat out cold. I have this on my car and I love it, great add on feature! :thumbup: