There’s a backlit icon of a simmering coffee cup on the 2012 SLK’s control panel that, for anyone unfamiliar with the latest in Mercedes-Benz safety gadgetry, is certain to cause confusion.

Could it be this particular well-optioned roadster comes with its own coffee maker? Or perhaps the symbol flashes intermittently whenever a Starbucks comes into view? Impossible to say, since the owner’s manual, a critical tome considering SLK’s techno-laden content, was AWOL.

“They’re frequently missing after the cars are returned so we keep them here in the office,” explained a Mercedes-Benz press-fleet overseer. The missing manual limited the range of plausible explanations to the ridiculous.

Fortunately, an experienced Mercedes-Benz brand hand came to the rescue, appropriately enough while parked outside one of the Seattle-based caffeine purveyor’s outlets. After admiring the SLK from top to bottom, he spied the tiny cup-and-saucer symbol and explained that it denotes “Attention Assist,” which is a safety feature that’s programmed to sense certain driving behaviours associated with fatigue and issues both visual and audible warnings to the driver suggesting he or she take a break.

The smell of fresh-brewed Pike Place Roast wafting out from the air vents could probably work just as well.

Attention Assist is a fine idea, but it’s hard to imagine anyone nodding off in what is one of the more exciting M-B models on the market and the best SLK that the German automaker has devised to date.

The SLK has steadily evolved since its 1997-model-year North American debut. The current generation now looks less like an inaccurate representation of its larger SL-class relation and, at least from the front, now resembles its twin. Both cars feature nearly identical upright grilles, headlight pods and extended hoods, along with similar retractable hard-shell roofs. Of course, what they don’t even come close to sharing is their respective price tags; the $56,000 base SLK is offered at less than one-half the wallet hit of the SL.

Of course the SLK lacks the new-for-2013 SL550′s 429-horsepower twin-turbo V8, but the 302-horsepower V6 and accompanying seven-speed automatic transmission in the SLK350 is no slacker.

The warp-factor model of the triumvirate is the SLK55 AMG that receives the full aero kit treatment, unique nosepiece and fancier wheels. It also sends its power to the pavement using a 415-horsepower 5.5-litre V8 and earns a 4.5-second zero-to-60-m.p.h. (96 km/h) time.

Within the SLK range, though, the 350 in my possession has a certain just-right feel. Around town, the V6 operates in a docile fashion, but can quickly flex its muscles when a squirt of passing thrust is summoned, or when attacking a freeway on-ramp. During these measures, the engine instantly clears its throat and delivers a distinctive, yet dignified growl while the seven-speed automatic imperceptibly kicks down into the appropriate gear. The SLK makes the entire process seem so easy and in no small measure enhances driving confidence.

Also easy is the two-seater’s power-operated conversion to convertible from coupe status. The trunk lid pivots rearward while the hard tonneau cover flips upward and the two-piece roof stacks into its containment spot, followed by the trunk lid resuming its original position. The whole lowering/raising sideshow consumes about 20 seconds.

The test model was equipped with the available Magic Sky Control, consisting of a glass roof panel that changes to opaque from clear with the flip of a switch. Also included is constantly adjusting shock-damping control and a faster-acting Direct-Steer system that reduces by 25 per cent the number of lock-to-lock steering wheel turns. About the only item of concern on the well-appointed SLK was its matte-finish Designo Glacier Grey colour scheme. The idea of an as-tested $78,500 Mercedes wearing what amounts to a really dull paint job might seem anathema to some buyers. It also carries a sternly worded missive warning of dire consequences should the finish ever be polished.

The SLK test stretched into a week of mostly sunny skies and light Pacific Ocean-scented breezes on Vancouver Island. In other words, perfect sports-car weather in a part of the world attracts plenty of them.

And likely not one of their grinning drivers, including one SLK350 pilot in particular, required a cup-and-saucer advisory to keep the adrenaline flowing.