i've noticed at the shops that the cheaper alarm systems don't
come with their own relay (they utilize the existing one), the
expensive ones do. does anyone know whether this factor is
important?
hmmm... actually the relays are used as starter kill. As long as you can get the starter kill, regardless whether expensive or cheap alarm, they are the same concept so should be okay.
Few months ago, prior to New York Auto Show, Jaguar has borrowed the city's iconic Park Avenue tunnel to exhibit (or break the silence in) Jaguar's new F-Type SVR coupe.