Dexcom only makes CGMs, not pumps, so they've partnered with Tandem.

Dexcom and Tandem delivered the auto bolus correction doses years ago. Surprised Medtronic hasn't caught up yet.

Edit: also, the fact that you're so successful with Medtronic makes me think that you'd handle the switch better than most. If you're a good shot with iron sights, you'll be an even better shot with a scope.