All of those r good. DEI is the big dog of the alarm industry. But truely any alarm is only as good as the install if your gonna do it take your time and never say " i'll just fix that later"! Do it rite the 1st time and be sure. If you are gonna take it to a pro then without anyone watching tip the installer 1st not after what is he gonna do for you as you are leaving, tip em 1st then he will be more than happy to go the extra mile for you while working on your car!