The RX450h+ is the plug-in hybrid version of Lexus' popular midsized luxury SUV. It’s quicker and quieter than the RX hybrid, and has a decent EPA-estimated 37 miles of electric driving. Once the battery is drained it delivers the same 34 mpg as the regular hybrid. It takes about three hours to charge the 18.1-kWh battery on a 240-volt connection. Power is plentiful, but there’s an uncouth growl when the hybrid system transitions from quiet electric operation to the four-cylinder gas engine. In other respects, the PHEV is similar to the rest of the RX line with a comfortable ride, sound--but not sporty--handling, and a quiet cabin. The front seats are comfortable and the rear seat is roomy. The infotainment touchscreen isn't the most intuitive, and the electronic door latches and gear selector take acclimation. We like the standard head-up display, but interacting with it through the unlabeled steering-wheel buttons is fussy.