This is no trivial matter. After all, why would you buy an E Coupe when for about the same money you could get Mercedes' new E Sedan? The midsize four-door Benz is the standard by which all Mercedeses are measured. It's the company's best-selling model worldwide and the unimpeachable choice for every Beverly Hills tennis pro and real estate agent who ever lived. The E Sedan is bigger, more practical, more richly equipped. It's a car every bit as tightly nailed together, offering performance nearly equal to that of the sports-minded E Coupe. Only one reason: The E Sedan is beastly looking. In a recent review, I said the sedan was 'very proper and Swabian and gloriously unartistic.' In the months since, my opinion has only soured. I hate the way the car slumps at the head like a pole-axed buffalo. I loathe the over-shaved, winnowed taper around the grille. I detest the graceless quadrangle of windows on the sides. I gag on the exaggerated accent lines on the fuselage that don't visually intersect with anything in particular. It's a terrific machine, but really, the E Sedan's homeliness has a kind of malign ambition about it. Meanwhile, the E Coupe, the replacement for the long-lived CLK Coupe, is lovely. The grille -- with two horizontal bars supporting a softball-sized Mercedes emblem -- looks tougher, more masculine and declarative. The black-mesh intakes in the lower bumper are deeper and more aggressive. On the E Coupe, the accent lines actually give the shape some visual velocity, converging like metal contrails at the rear of the car with the decolike fender flares. The roof line arches exquisitely over a pillarless canopy (that is, there's no 'B' pillar roof support). Low, wide and rakish, the E Coupe design has an organized, coherent energy about it, a godly brow to the E Sedan's low forehead. And the impression of sleekness is borne out by physics. Mercedes claims this is the most aerodynamically efficient series production car in the world. By the way, those fender flares, according to Mercedes propaganda, recall the company's Ponton ('pontoon') cars of the 1950s. I'll take Mercedes Trivia for $1,000, Alex. And now for some factoids: The E Coupe, like its sedan sibling, comes in two flavors: E350 Coupe, with a 3.5-liter, 268-horsepower V-6, good for a 0-60-mph dash of 6.2 seconds, or E550 Coupe, with a 5.5-liter, 382-hp V-8 that will accelerate to 60 mph in a damn respectable five seconds flat. Like the sedan twins, both coupes have a seven-speed automatic transmission with manual-shift buttons on the steering wheel. The E550 Coupe gets slightly bigger brakes, wheels and tires as well as adaptive suspension (Mercedes holds back the air suspension found on the E Sedan). Not surprisingly, the E350 Coupe gets better fuel economy: 17/26 mpg, city/highway, to the E550 Coupe's 15/23 mpg. The V-8-powered car is base-priced at $54,650, while the V-6 car starts at $48,050 (both cars are about $2,000 less than the comparable E Sedans). Having digested this number salad, you could be forgiven for thinking that the E Coupe is, in fact, a two-door version of the E Sedan. But that would be too easy, wouldn't it? Despite the nomenclature and the many similar styling cues, the E Coupe is actually based on the smaller C-class chassis. That's not a bad thing: What you have here is a compact frame stuffed with the guts of a big performance sedan. This is a taut, ferocious little luxury tourer, with excellent brakes, high-strung steering and engine torque that comes on like Man o' War in the final furlong: 391 pound-feet of torque between about 2,500 rpm and 5,000 rpm. The E550 Coupe weighs 251 pounds less than the sedan. Combined with the highly dexterous seven-speed gearbox, the E550 Coupe will pass just about anything on the road. Simply kick down three gears, pull out the whip and start wailing. At these moments of throttle-tromping honk, the E Coupe's exhaust note is big, brassy, an ornery and operatic cackle. Beautiful. But take your boot out of the accelerator, and everything goes quiet. A benefit of the low aero drag is, of course, low wind noise. At relaxed speeds, the E Coupe's cabin ambience conjures a plummy hushed purr. How's it feel? The steering wheel is like a stitched-leather barbell. The tactile feedback through the seat and floor is one of heavily damped, cold steel structure attenuated through the fine-grain leather. The E Coupe's interior gets a dose of high-end upholstery that is usually associated with Mercedes' premium AMG-edition models. This is a four-seat car -- that is, two bucket seats in back -- and while access to the rear is good and headroom under the low roof is surprisingly ample, the rear seat space is for occasional use only. That's another reason to prefer the coupe to the larger sedan. It's a private reserve. Between its compact size and forward-cabin focus, I found the E Coupe to be as intimate as lacy underthings. Loaded with new standard features -- pelvic and knee air bags, driver drowsiness sensor, panoramic roof -- and kitted with ample Mercedes luxury, the E Coupe is fast, athletic, beguiling. For anybody weighing the choice between four doors and two, it puts a gorgeous thumb on the scales in the coupe's favor. E-mail Neil at dan.neil@latimes.com. 