AG4 all the way. AG4 ensures that the only way your car will be gone is if they tow it. Im not really a fan of the pager systems, I think they are more stressful than anything. Cause if ur in the mall, and ur pager goes off, ur trippin' thinking somebody's trying to get ur car and what are you gonna do, run through the mall, through the parking lot to check on it? I'd rather have peace of mind w/the AG4 and an autolock just for sh*ts and giggles.