If you plan on buying another alarm there are a variety of options. Just understand that there is not a fool proof alarm available. A basic install on an alarm can be easily defeated in 2 ways. One, break window, pop hood, disconnect battery. Two, break window, pop hood, disconnect siren, listen for the relays clicking on the alarm brain box and disable the brain box. These two basic methods can get a thief past most alarms. The best that you can do is try to out smart them. Here are a few ideas.
1. Buy a back up battery. When a thief rips your battery cable off, the alarm will continue to sound.
2. Pay a little extra and have the installer pull the dash and install the brain box where it is not accessable.
3. Be creative when installing the siren. Try not to place it where the wires can be easily reached. If possible, have two sirens installed. Also, the vehicle's horn is loud and not as easy to disconnect.
4. Have relays and wiring installed so that the alarm flashes the parking lights and head lights. Just make sure the relays are not easily accessable.
As for the best alarm, check out Clifford, Alpine, or Ungo. Just a few off the top of my head.
5. Buy a paging system to install on the alarm (your in luck! I have one for sale!). When your alarm is tripped, or even if it senses a bump (depending on the alarm) you would be sent a page.