I see the deactivated immobilizer like Chooch, but I can also understand the view of sosxfire and those who feel uncomfortable with it.
I have thought a little bit about the concept and I have come to the conclusion that I can design the module to have both.
Either the immobilizer is always deactivated or you can buy an option where an RFID reader and 10 pieces of RFID tags are included.
Then you can teach the tags to the module and then you have always to hold the tag in front of the reader before starting.