Mine came fitted by the dealer when new. Doesn't appear to go off without provocation and the battery drain seems reasonable. I needed it for insurance but not sure how much use it really is given that certainly mine can be bypassed easily with the blanking plug that's fitted if you don't have one. Overall, happy with mine.
Mine saved my bike when it was attacked. The ignition can be bypassed with a screwdriver, especially once they break the steering lock, so the immobiliser as part of the alarm is great. Immobilisers are only std from 2013.
I had a 3rd party one. Stupid thing malfunctioned and the immobiliser refused to let my bike start. Had to get it recovered to my garage. The guy showed me how he could shut it up before it went off by shoving a cloth over the tiny speaker then disabled it ridiculously fast. Its not permanently disabled on mine as it was broken and after watching him disable the whole thing I wouldn't invest in one. Having said that, I am thinking of getting a tracker which I think would be far more useful (especially if well hidden). I'm just going to buy a stand alone tracker unit, not a service. They seem pretty cheap these days.
