Interesting! I have been mainly using my Codefree, reserving my TEE2 for doing a second reading when I don't like the look of the first. But recently I seemed to be getting a lot of unexplained high readings on my Codefree, so I switched to my TEE2 full time and since then my readings have been impeccably low (well, almost!) I do have some misgivings. What if my TEE2 is giving inaccurately low readings and my Codefree was correct all the time? But cheered by those low readings I find it much easier to be really strict about my low carb diet. The high Codefree readings left me intensely discouraged and tempted to comfort eat. So maybe even if my TEE2 readings are fictitious, they are helpful psychologically.