Have wasted sensors that stop responding or do not initialize. Not to mention, the sensors are EXTREMELY EXPENSIVE!!!!Have to calibrate 2-3 time per day!!! The good thing is it makes me finger *** and test my blood more now than I did prior to going with the CGM. What good is the SENSOR if I have to finger *** that many times per day/night? Now, my 670G is now having an error where I have to rewind and reload several times per vial! And, the cheap tubing and cannulas are EXTREMELY EXPENSIVE as well!