Does this unit have no built in power supply thus requiring a power brick? Trying to decide between the purchase of a Resmed S8 Elite or Respironics REMstar Pro M.

has also used a previous model S8? Is the II noticeably quieter or is it just "marketing"? I am thinking about replacing a (5) year old machine with a S8. The S8 II is not yet available in the U.S. and I can wait if the new model is much quieter. The machine being replaced is a Bipap-Pro that is set...