mines an import and still has the imobiliser one way to find out is take the plip out of the key then see if it will start,i've got an autowatch alarm on my 172 and it has proximity sensor which was £280,i wouldnt bother with a clifford a few of my mates have got them and imo they are overpriced and play up a lot
and for people who reckon cliffords work fine if fitted properly i've been told by 2 alarm fitters that there not that good