I had ours fitted by GAP, they were pretty good and TBH it's the only thatcham alarm I've had that lasted more than 2 years!
For Thatcham read SCAM, qualilty usually quite poor, features pretty rubbish, what use is it to have an alarm that locks your baby in the car whilst you are putting up the pram :roll:
They don't make your car much leass stealable TBH, people only fit them because insewerance companies are so stupid.