Ever since Volkswagen announced its various clean-diesel-related initiatives, including the Jetta TDI, the SUVs, the R8, and so on, I've been waiting to see reports on what these cars actually drive like. Road & Track finally has one for the 2010 Audi Q7 3.0 TDI—and it looks like it's really capable of reducing both fuel usage and emissions.

The report said that Audi's direct-injection diesel makes 221 bhp and a stunning 406 lb.-ft. of torque from 1750 through 2750 rpm. "Audi touts its AdBlue urea-injection system as allowing the company to offer the cleanest diesel in the world," the report said; the first of these U.S.-bound engines featuring this technology is 50-state legal. "To put the latter into perspective, their NOX limit will equate to 0.13 grams per mile. The current California limit is 0.07 g/mi. In Europe's favor, its 2014 particulate limit is a bit tighter than our current one."

The TDI version of the Q7 should cost about $2,000 to $3,000 more than the regular gas-powered base car, which begins at $42,500, the report said. It's expected to deliver around 25 mpg on the highway, compared with 17 mpg for the gas version. That's fine, but I still think the market will be large enough for both the clean diesel TDI and the Q7 hybrid that Audi inexplicably decided to can.