The Jaguar XK is the modern interpretation of the iconic E-Type coupe from the 1960s. Like its predecessor, the XK is a luxurious grand tourer for an affluent customer who desires a British alternative to the Porsche 911 or BMW 6-Series. With a standard 300-bhp V-8 mated to a 6-speed automatic, the XK is quick but no match for its German rivals. Jaguar does offer a 420-bhp supercharged V-8 in the XKR, which is better suited to take on its competitors. The XKR distinguishes itself from the standard XK with unique alloy wheels, upgraded brakes, unique exterior and interior trim, and sport seats. If that isn't enough, a special Portfolio model adds 20-inch alloy wheels, 6-piston/4-piston front/rear brakes, premium 525-watt audio system with B & W speakers, and special Celestial Black metallic paint. While the standard XK is an attractive coupe, it lacks the performance credentials required in this rarefied segment. Instead, the more exclusive XKR is probably the best choice from a price/performance perspective. The range-topping Portfolio doesn't offer much to justify its nearly $100K price tag, especially considering that the 500-bhp BMW M6 is in the same bracket.