I'm going to actually try it out in a few minutes.
I am the proud owner (leasee) of a Respironics Remstar Auto M Series. The DME brought it by at 1:00 pm and showed me how to use it. It even works with my emergency backup battery which is a super good thing. It is definately half the size of the loaner machine.
I'm looking forward to lugging it around the airports next week.