I was one of the first T1 diabetics to start using CGM in the UK when a friend of mine brought a Dexcom Seven back from the States for me, before they were licenced over here. After upgrading to a Dexcom Seven Plus later and 3-years ago, going onto the Animas Vibe, using the Dexcom G4 sensors on and off for a few years now. I have recently had the pleasure of using the Abbott Freestyle Libre, I am now considering to switch to the Libre. I still have my Vibe so can easily go either way, but I am leaning towards the Libre and here is why. As has already been mentioned, the Dexcom transmitter is disposable when the internal battery dies! This is a money making scam and Dexcom know it. Because I am unable to fund 100% of my year with CGM coverage, it works out expensive when you only use 6 to 10 sensors on a single transmitter. Another issue with the Dexcom is the need to calibrate the sensor every 12-hours with blood tests! Like many people, I dislike the finger prick tests and really want a break from blood testing when I am wearing a CGM. Then there is the sensor life. The Dexcom is designed to last for 7-days and while they can be rebooted, trying to keep it in place for weeks can be a real challenge, especially in hot and sweaty conditions, or if you swim regularly. I found myself using Tegaderm film to keep it in place, dry and sterile. My longest sensor life was just over 3-weeks, but the last week was fairly inaccurate with several periods of ???. Living in constant hope of keeping the sensor in place and that it still keeps working day after day is a pressure you don't need. Calculating the price of the Dexcom based on what you might expect from a sensor is unreasonable. If it fails on day 8, customer services will not replace it. Plus if you only use CGM from time to time, the extra pressure of knowing that your transmitter is slowly dieing in a drawer somewhere is also no fun. It tempts you into spending above your budget and buy more sensors than you can afford to get more use out of your expensive dieing transmitter. The Dexcom alarms used to wind me up too. My wife started sleeping in the spare room, especially when the Dexcom started becoming inaccurate. It kept alarming that I was falling too quickly or was below 3.4, but subsequent blood tests showed that I was really 6.4 mmol or similar. You end up turning off all alarms! As the Libre needs no transmitter, it allows you to chill out, leave it for a month or two, buy a sensor, use it and then leave things for a while again. Cheaper long term costs if you don't need full CGM coverage. The Libre requires no calibration, so no blood tests required. Okay officially you are meant to do a blood test before giving yourself insulin, but I have found the Libre to be very accurate and after gaining my confidence, I would do a random test each day to check it was still fine and then used it's data to treat myself. The sensors stick very well. In fact so good, I found it really hard to detach from my arm! It is designed to last for 14-days, unlike the 7-day Dexcom, so peace of mind if calling customer support in week two or informing my diabetes nurse that I had rebooted my Dexcom and was using it for longer than I was meant to. If you are a pumper and have access to reliable CGM, you ideally want to be setting up your pump basal rates and getting to know how your body reacts to certain foods/carbs, which should allow you to opperate without a CGM for extended periods. The CGM can then be used to double check your control from time to time or when your life routine changes significantly. Though in my opinion, CGM provides T1 diabetics the full picture and allows them to correctly manage your blood sugars. It should be a minimum standard of care for all T1 diabetics. If only it was more affordable!