I can't imagine there are very many manufacturers of the new aftermarket Auto-Level compressor assemblies, so I'm lead to believe they are just rebrandings of one make. The ones I'm looking at are Dorman, Arnott and Cardone. They all look identical (at least in their online photos) and all have "limited lifetime warranties", depending on where they're purchased. I'm not so worried about a warranty since I'd be surprised if I put 10K miles on my Tahoe in a year. The Cardone 4J-0003C is $145, the Dorman 949-001 is $167 and the Arnott P-2793 is $195. All three are available through Amazon Prime so shipping isn't a factor. Is there any actual difference(s) in these? I see Dorman has a 949-099 for $193. The note say it includes a thermal switch and round and square connectors, which I assume are adapters for it to fit the '01-'14 instead of just the '01-'06 or '07-'14. But I'm not sure what that thermal switch is about. Is it an added-on improvement over the OE design? Is it worth the extra $30?