As mentioned, I bought my car from Sutherland, and get it serviced at Chatswood. 15k service was brilliant even though I bought my car from another dealer. As Dan said, it is my understanding that Lexus Australia get charged regardless. I have the free servicing for "X" amount of time and due to Lexus Aus paying, not the dealer, I am able to take the car anywhere for service.
Another member, Cevu, had his whole EMV replaced under warranty through another service provider. He was wrapped!!
In short, I don't think you will have hassles in my opinion.
Ah, I missed that while I was trying to read through quickly on my ipod!
I'm going to book it in for later this week