Keith created it two years ago as a one-shot commemoration of the powerful XK engine.

FORBES: My Brother-in-Law, The Designer

Much of the sweetness and delicacy of the XK has been scourged from the XKR-S's suspension.

WSJ: 2013 Jaguar XKR-S Review: A Genteel Tourer Goes Rough-and-Ready | Rumble Seat by Dan Neil

The current-generation XK, a grand touring coupe that debuted in 2006, is, by contemporary standards large, soft and not exceedingly track-friendly.

WSJ: 2013 Jaguar XKR-S Review: A Genteel Tourer Goes Rough-and-Ready | Rumble Seat by Dan Neil

Father and son Oscar and Ernest Ruelas of Ruelas Coachworks in Whittier, California were on hand with a beautifully restored 1958 Jaguar XK-150 S Roadster.

FORBES: The San Marino Motor Classic

Yet, I was a bit reluctant to hand over the keys to the feisty XK. But, soon the XKR-S took its place in a row of Roll-Royces, Jaguar E-Types and Ferraris.

FORBES: 2012 Jaguar XKR-S: The Road to Pebble Beach