Fisker Karma Vs Porsche Panamera

With sticker prices of more than $100,000 apiece, the Porsche Panamera and Fisker Karma luxury sedans probably aren't on your shortlist of cars to buy. But each has created a lot of buzz in its own way. Both are four-door, four-passenger cars with eye-catching, coupelike styling. But that's where the similarity ends.

The Karma is a plug-in, extended-range electric car, similar in concept to the Chevrolet Volt, and is the first car built by the American start-up Fisker. With a full charge, the Karma can go gas-free for about 38 miles, delivering the equivalent of 66 mpg overall (1.96 miles per kilowatt-hour). Once its battery is depleted, a raspy turbocharged gasoline engine kicks in to generate electricity for longer trips. When running on premium gas alone, the Karma gets 22 mpg. Actual fuel economy depends on how often the car runs on electric power. Driving a 50-mile commute on a single full charge yielded the equivalent of 44 mpg overall.

Of course, the sleek, 402-hp Karma is about more than gas mileage. We found its ride, handling, and braking performance to be sound, and interior materials are first-class. But it is plagued with flaws. Compared with other luxury sedans, its tight confines and limited visibility can make the cabin feel claustrophobic; a lack of conventional buttons and the worst touch-screen system we've seen make the dash controls an ergonomic disaster; and acceleration lacks the oomph you'd expect from a sports car.

The Karma had a rough start in our testing when it suddenly became disabled on our track. Fisker replaced the battery pack in our car and later offered replacements for all 2012 Karmas. But we've continued to encounter disconcerting intermittent glitches related to the gauges, warning lights, power windows, and radio. According to user reviews on the Web, we're not alone. Overall, the Karma scored too low in our tests to recommend.

The Panamera, Porsche's first four-door car, was warily received by some sports-car purists when it was introduced in 2009. But we found that our Panamera S, powered by a 400-hp V8, offers an inviting blend of performance and practicality that handily upholds the Porsche pedigree. It delivers quick acceleration and excellent handling. Passengers are coddled in a comfortable, quiet, nicely finished cabin. And a hatchback and folding rear seats add versatility. But the cockpit is somewhat snug, the cluttered controls can be confusing, the firm suspension isn't as comfortable as that in a traditional luxury sedan, and the low-slung roof makes it challenging to get in or out in a dignified manner. We lack sufficient reliability information to recommend it.

The Karma has two drive modes: The default, Stealth mode, uses up the battery charge first, then starts the GM-sourced 260-hp gas engine. The Sport mode uses the gas engine to provide full juice to the car's twin electric motors and lets you save battery power for later use, such as for city driving. The car takes almost 6 hours to charge on a 240-volt electric car charger, or about 16 hours on a standard household outlet.

Despite its quick acceleration times, the Karma feels sluggish, especially off the line, because of its hefty weight and the gearing of its single-speed transmission. Conversely, the Panamera feels effortless, and the seven- speed automated manual transmission snaps off smooth shifts every time. It returned 20 mpg overall on premium fuel.

There's something invigorating about the basso burble of the Panamera's V8; the Karma emits only a series of electric hums, whines, and clicks until the gruff engine starts.

Two things stand out inside the cars: the gorgeous materials and tight interiors. The driver's position feels narrow in both cars, and the Fisker has barely adequate head room. The small windows and high rear deck severely limit outward visibility in the Karma, and the Panamera is only slightly better. At least their backup-camera systems work well.

Rear passengers in the Porsche can stretch out; in the Fisker they need to wedge their knees and feet against the front seatback.

The Porsche's controls, with an array of small buttons, seem overwhelming at first. But its touch screen is easy to read. The Fisker replaces almost all controls with a poorly designed grayscale touch screen that is slow to react, unintuitive, and hard to read.