After reading many of your positive comments about Dexcom's accuracy and after wearing a rep's loaner for 2 weeks with excellent results (compared to my old Medtronic sensor worn at the same time), I bought the Dexcom. It worked great for 5 days. Then I had a meter reading 60 pts. different than the Dexcom. (I had been doing no exercise; just sitting at a desk.) Since the arrow was level, I decided to calibrate. 20 minutes later I got "???" I read the manual that indicated to wait up to 3 hours for it to self correct. I also called the help line and was told the same thing. For 2 1/2 hours there were no numbers, and then when they reappeared, they were way off for the next 18 hours (up to 100 pts) despite my calibrating several times. I removed the sensor and put on another which started off not too good either but is improving. Any ideas on what I may have done wrong?
(I posted this also on a different forum by error.)