I'm the maintainer of a proprietary C++14 RTOS for work. What do you want to know?
The advanced template techniques (and to a degree, I'm throwing type deduction in there too), when treated skeptically do lead to more efficient code. It's easy to go off the deep end though, which is why I said "when treated skeptically". As for lambdas, we have an entirely asynchronous OS, so they're really nice for callback glue.
EDIT: Binary literals actually come up way less than you'd think, even for deeply embedded (I think the smallest thing we ship on currently is 16KB of RAM). Everyone here knows hex like the back of their hand.