I honestly can't answer your question, but I think many of the expensive probes are probably "cheap Chinese K-Type probes". I have always bought my probes from ThermoWorks. At least my Thermapen is made in the UK by nice Limey folk.
Hog Mountain Brewing Co.
Tap 1: Robust Porter
Tap 2: Pliny The Elder - Kicked the bucket :(
Tap 3: Munich Dunkel - almost gone
Conditioning: Petite Pliny IPA
Secondary: House Favorite APA (10gal)
On Deck: American Brown
"Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut."