That information is outdated, Puritan-Bennett has become Covidien and their current machine is called the Sandman Auto. I got mine as a warranty replacement when my PB 420E died about a year ago.
It is fully data-capable (shows a lot of data just on the screen, too) and I ABSOLUTELY LOVE it. I can't hear it from about 3' away, let alone my husband hearing it, and it's tiny and lightweight. It has a built in heated humidifier (you can also get it without). The only problem is that it makes noise if the humidifier tank isn't set correctly on the heating plate. It doesn't have exhale relief or auto-on, however, and you can't pre-heat the humidifier. I've gotten used to all those things (the 420E was the same way) but it might bother some people.
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