I started with Medtronic's CGM about 5 weeks ago. I was calling their help line with questions about accuracy and skin issues almost every day for the first 3 weeks. They are always very nice, but have told me that the learning curve is about 3 months. Sad, because the pump part was so easy to learn. The hardest thing for me was trying to figure out when my glucose levels would be stable enough to calibrate. I put my last two sensors in at night, silenced all alarms, and waited until I woke up to calibrate. Both of these sensors have been much closer to my actual readings and patterns. The downside of course is not being awakened in the middle of the night if low. If I had done this as a trial I would not keep it, but unfortunately, a trial was not offered and I have paid a lot of money, so I am sticking with it. Maybe that's their marketing ploy? It is getting better. Good luck.