I frequently hear that Dexcom's CGM is more precise than Medtronic's. And Abbott stopped selling theirs in the U.S. (I don't know exactly why). Therefore the dominance...
From what I've heard (industry rumors), Insulet bought/licensed a CGM company/technology, has now integrated that into the pod, and is trying to get that this single-unit closed-loop system approved by the FDA/CE. Apparently hey are currently running animal trials with successful results.
Gil -that is interesting. The CGM side of life took a bath when Abbott stopped selling the Navigator 1.5 in the US. There are many rumours as to why. Anyhow, that aside, the Navigator still has the best accuracy and they are now launching / launched the Navigator 2.0. So worth a look maybe.
Don't remember what had the Dexcom Seven plus, but Dexcom G4 has a spring loaded inserter. Medtronic Enlite, here in Europe, according to users I read has a very bad reputation for precision and accuracy: it drives you crazy. Only a few people are happy, but they already had steady BGs.
Instead Dexcom G4 has almost unanimous good reviews: no pain, lasts often 20 days with very good accuracy (+-15 mg/dl), starts soon to give good readings and is water proof (not the receiver...)