CGMS - this is the only "integrated" system so I went with it as I could continue to wear one pump/monitor. I reccommend seriously looking at other options or planning several hours/week on hold and then the phone iwth customer service. Many sensors seem to be "bad" but when you request the report back on them, they are all evaluated as testing out ok. I've found that it depends on the box. They have been good about replacing the ones that don't work (as they shoudl at $30/each). I love the system when it's working, but it doesn't work as much as it does work.