Men are very useful beings in general, but not so great when they don't want to talk to the salesmen. Today I went back to the snooty appliance store alone and got some real, useful information from someone who really seemed to know his stuff. (I have a pretty good BS meter which has been ringing off the hook with most of the appliance salesmen I've talked to, which may be part of the afore mentioned man's problem...)

Answer: Frostless freezers ALL raise the temperature in order to defrost. There's no other way they can do it. The guy even explained the machinery but I can't reproduce it accurately.

The thing that's different about today's top frost free freezers and the old self-defrosting freezers is that they use an evaporator to remove the moisture that creates the frost. By doing that they limit the amount of frost and therefore limit the length of the defrost cycle.

It is, however, still true according to him that your frozen food will not hold as long in even the best frost free freezer as it will in a manual defrost unit. He said most people shudder at the thought of having to plan to have their freezers empty so they can defrost them, then do the work of defrosting. They care more about that than their food. If you want to hold your food at top quality longer you're just too unusual to be served by the top brands.

The Sub Zero also is the quickest freezing freezer they have (comparing GE, Thermador/Bosch, etc.). He's done experiments :) I can't remember for sure, but I think the Sub Zero has a sensor which knows if there's something not frozen in the freezer and turns on the cold. Whereas the Gaggenau (I don't remember if Therm./Bosch do) has a button you can push for freeze now.

I did know that on the Sub Zero refrigerators the cycling right after it closes that makes it so hard to reopen for the next 10 seconds was because the air pressure inside was equalizing. What I did not know is that part of the reason for this is that the cooler turns off when you open the door so that it won't suck in warm air from the room.