an alarm is as only as good as it is fitted. any Cat 1 alarm is going to be good as it has to be assessed in order to achieve that status, the problem is the wannabe hero's who install them, when i bought my cab it had a cat 1 clifford 800 installed by a pro certificate too.
great, the door light didnt work, the carpet was torn on the install as the numpty just ripped the edges. 2 weeks later i switch on my fan hear a pop and smoke from under the column is seen. closer inspection the idiot had wired fuses directly under the steering column with incorrect gauge wire and even stuck bits of wooden pegs in the connectors to keep them in, even the door solonoids were jammed up with carboard to stop em moving.
my advice make sure its a pucka install and theres installation warranty.