I've worn insulin pumps for more years than I care to count. One of the things I'm looking for in my next pump include a significant reduction in the number of button pushes to accomplish routine things like a bolus calculation and delivery. My current Animas Ping is a poor performer in this facet. For instance, I cannot arrow-up from the top of a menu to access the bottom menu item. Bolus selection is done on an arrow-up scroll to serially access the dose I want. I'm plenty tired of the overshoot-undershoot-overshoot circus. The t:slim addresses this issue.
As I age (I'm 58 now), I increasingly value better resolution screens. The ability to read my pump during the night without finding my glasses is a definite plus for me. Also, my current Animas pump is virtually unreadable in bright sunlight. I'm told the t:slim is readable in bright sunlight.
The rechargeable battery is a great idea if it delivers as advertised. Tandem's website includes videos from beta users that say they charge their batteries while their pump is disconnected from then during shower time. If it is a reliable quick charge, I see that as a green plus.
I, too, am worried about the screen ruggedness. I've owned iPhones for 4 years and I've dropped my phone from my pocket onto a paved surface as I was getting out of the car. The screen did not break. If the unit can survive short falls and they provide reasonable customer service, support, and warranty policies, I could probably live with this risk.
Finally, I am thrilled that at least one pump manufacturer values design and the user interface. I hope this company and its product meets with success.