Dear Optus,
If you're not going to deliver all my phone messages to their intended recipients, whether it be from any of my current handsets, I expect to be compensated with a lower monthy rate. This seems fair.
Sincerely,
Ruben
PS: SingTel, please whip your boy into shape. And get him to stop with the "unlimited" advertising too, you might get into trouble for that with a four letter acronym.