What a quick little crossover! Honda's first-ever U.S.-market turbo is a pretty good one, generating gobs of mid-range torque and providing a swift kick in the back when taking off from a light. I'm not so fond of the RDX's inability to put down all this power, as evidenced by frequent wheel spin at launch accompanied by a bit of torque steer. Opting for SH-AWD would likely render this complaint moot, and would put the price of this loaded Acura at $38,430 - about the same as a base Audi Q5 lacking features like navigation and Xenon headlights.
The RDX is aging only okay, I'd say. As David Zenlea points out, the interior is not exactly plush, and the navigation system interface is not great. I'm especially put off by our particular test vehicle because it's front-wheel drive, not all-wheel drive. When you're selling a premium crossover, to my mind all-wheel drive should be standard. Hit the accelerator when you're at an intersection in a $36,000 crossover, and you really don't want torque steer. The lack of all-wheel drive was exacerbated during the time we had the RDX because we had a lot of fresh snow in Ann Arbor.
I didn't spend much time driving the RDX, so I'll take this opportunity to register my complaint about Acura's stereo interface - in particular the convoluted operation of the channel selector (the same as in the ZDX we recently test drove). I'm a huge fan of dials, one for the volume, and one to select the radio station I desire. In the Acura, you have to first select the audio button so that the screen shows you the audio information. Then you have to scroll to one submenu, then to another submenu, and then select a button before the big dial in the center of the console can be used as to change stations. It may not sound so horrible in print, but in practice it's a pain, and it means you're your eyes are off the road as you're attempting to perform these maneuvers, which is never a good thing.
The Acura RDX's turbo four is still a bit of an anomaly in the small luxury SUV/crossover segment. It's peppy but it certainly isn't as fast as it's V-6 equipped competitors. This is an acceptable trade-off for the much higher fuel economy returned by a four-cylinder engine, right? Well, not in this case. Despite being much lighter, having far fewer horses, and having a significantly lower engine capacity than the V-6-equipped competition, the RDX manages only marginally better fuel economy. The Acura's combined average is 24; a number matched by the BMW X3 and the Lexus RX350 and only missed by 1 mpg by the Infiniti EX35 and the Audi Q5.