I see a lot of the square black models, the Excalibur? Is there a big difference between that and the old school round ones? I was going to get a round one because they are less expensive, just making sure it has a thermostat, will this work for raw food cooking?

My family uses this one, we are about 80% Raw and it is perfect for us!

http://rawpeople.com/store/dehydrators/good4u-dehydrators-6-trays.html

Hope I helped you on your raw journey!