There are some remote starters that use the factory remote but the range of the factory transmitter and receiver is poor compared to the aftermarket ones that come with different transmitters.
If your has PK2 just under the rubber part then you have a transponder that will require an additional "box" to bypass the security system. Be prepared to pay about $50 extra and the installer may require that you sacrifice a spare key to go in the box.
I'd suggest to stay away from Bulldog and Auto Command product. The reliability on the units are not as good as some of the other. Viper, Presteige, Code Alarm, Ungo (maybe) are a few well known units and are good quality.