For those who desire an understated luxury vehicle–one in stealth mode–both the RX 350 and RX 450h hybrid models should provide more than satisfactory performance that is both refined and responsive without getting out of hand. That may not leave much room for excitement–or agility–since performance plays second fiddle to comfort and refinement in these models.
The 2014 RX's powertrain lineup is a carryover from previous years. The standard RX 350 comes with a 275-horsepower, 3.5-liter V-6 paired to a six-speed automatic with standard front-wheel drive and optional all-wheel drive. Even in heavier all-wheel-drive models, the engine provides more than enough power–feeling strong, confident, without enough gusto to pass smoothly and dash away from stop lights quickly, with nearly perfect shift quality.
Hybrid Lexus RX 450h models pair a 275-horsepower, 3.5-liter Atkinson-cycle V-6 with a version of Toyota's Hybrid Synergy Drive—one that, interestingly, electrically drives the rear wheels in all-wheel-drive form. Drive the hybrid gently and you'll glide from stops in electric-only mode, with the V-6 almost imperceptibly kicking on at 20 or 25 mph. Drive it a little more rapidly, to go with the flow of traffic, and the V-6 thrums on and off in the background, with the continuously variable transmission generally keeping the revs well below 2500 rpm unless you're close to full throttle.
In all, this is one of the most numb, isolated driving experiences in a hybrid--a good or a bad, depending on what you're seeking--although there are a few vibrations and some engine noise here and there. New for 2013 was a Sport Mode that gives you revised throttle mapping (with more aggressive tip-in) plus different transmission shift points that let the engine rev a bit higher. We haven't yet driven this version, but check back for updates.
The RX carries itself over the road with the same sort of muted, comfort-oriented feel that you'll find in the brand's other conservative models like the ES and LS sedans; the down side of this is that there's really no feedback to speak of through the steering wheel.