Recent tests of hybrid versions of the highly rated Toyota Highlander SUV and Nissan Altima sedan show that all hybrids aren't created equal.

Toyota Highlander Hybrid. The 2008 Toyota Highlander Hybrid SUV performs much like the regular Highlander, our top-rated three-row SUV, but got 24 mpg overall in our tests vs. 18 mpg. In the AWD version tested, the V6 engine, three electric motors, and battery pack produce 270 horsepower, the same as the V6 engine alone in the regular Highlander. You can choose an "Econ" mode, but it makes throttle response much more sluggish. The "EV mode" (EV stands for "electric vehicle") works in stop-and-go traffic and deactivates above 25 mph or whenever it thinks it should, which is often. The 2008 Toyota Highlander Hybrid Limited SUV costs $43,770, $5,192 more than the regular Highlander.

Nissan Altima Hybrid. The 2008 Nissan Altima Hybrid family sedan falls a little short of the standard Altima, our top-rated family sedan. There's a jerky transition when the four-cylinder gas engine starts and stops by itself. The battery pack eats up most of the trunk space and keeps the back seats from folding. The hybrid does accelerate slightly faster than the regular four-cylinder Altima and got 32 mpg overall vs. 25 mpg. Stability control is standard. But the hybrid costs $28,225, or $5,520 more. The $27,010 Toyota Camry Hybrid, with 34 mpg and higher performance scores, is better overall.

CR's take. The Altima gets better mileage; the Highlander drives more smoothly. Reliability is still unknown, so we can't recommend either hybrid.