Before going with any alarm company make sure you check out some basic stuff like how long have they been in business, it is amazing how many smaller companies are "authorized dealers or installers" and they don't always hire the best people. I know because I am a detective that just shut down a scam security company that had files from the other scam security company that they bought out.
How do they maintain their records? Do copies of your files including address, password, and credit card into ride around in some service guys car in case you need assistance? One nation wide company does that practice and the car was stolen AND they didn't notify their customers for fear of bad press.
Don't ever get a security system from a telemarketing outfit. Just trust me on this one.