How kuch is it costing you if you dont mind me asking? You can get a cat 1 alarm with immobliser fitted for 250 (toae ai606) or cheaper. I had mine fitted a few years ago and i paid around 240 for it i think
Obviously thats what an installer would charge now but most of the mk3s on the road now are only worth twice that much.I ripped my alarm out yonks ago, more agro that it was worth. Still got the Cat 1 immobiliser though...