The ES 300h is more aerodynamic than an RX so that helps MPG. Because the ES is lighter than an RX, it still gallops slightly on bridges, but significantly less than the RX.
Compared to the RX, the ES is super quiet at Interstate speeds.
The ES has a 5 star frontal Driver and 4 star front passenger rating per the window sticker.
The NX 350 window sticker claims that it has not yet been rated, although you can find sites on the internet that claim the NX has a top rating for crash safety. No clue on that one.