I decided to go with the Tandem T:Slim X2. Partly because I love my Dexcom and didn’t want to downgrade to the Enlite that comes with the Minimed. But also because I think changing every two days may be better anyway (so wouldn’t need the larger capacity T:Flex). The upgradeable firmware is doesn’t hurt either. 
UHC will pay 100% for of the supplies, so I paid for the pump ($4,300) and it should ship on Monday. I am quite grateful that I am in a position to pay out-of-pocket to go with my preference.
They are sending me the t:90 9mm infusion set, though I plan on asking for samples of the others when I go in for training.
Thank you for the support and advice. Fingers crossed this works out!