First impression: The B-ED reeks of the same high-class domesticity as Mercedes' R-Class and M-Class breeders. Similar seats, same spill-resistant textures, mostly the same instruments and switchgear, including the knobby dealy in the center console to dial in navi, audio and vehicle systems. Love it or hate it, there, too, is Mercedes' 7-inch color display floating above ball vents in the dash center, looking like an abandoned iPad.

In any event, the B-ED is not weird. Actually, it couldn't be more familiar and obvious. The accelerator pedal might as well have 'Schnell' written on it.

Got kids? Got a garage? Commute to the train station? Don't want to have to park a big German blimp every time you go out? Believe me, if your first Mercedes had a plug, you wouldn't be missing a thing.

Redesigned in 2011, the B-Class (tall family wagon) has been unavailable in the U.S. (but yes for Mexico and Canada). As part of the platform redesign, different versions of the vehicle floor stampings were created to accommodate batteries or compressed natural-gas storage. The B will be available in the States only as an EV. That fact, it's fair to say, won't supercharge model sales.

Mercedes execs are realistic. When I asked project manager Anton Sonntag how many he thought the company could sell, he shrugged and said: 'As many as people will buy.'

The B-ED is, realists would note, a 'compliance car.' The phrase refers to a low- or zero-emission vehicle model, built in whatever numbers necessary to satisfy some portion of California's clean-vehicle quota and typically sold only in California and 10 other clean-air states. The California Air Resources Board obliges major manufacturers to sell an incrementally rising percentage of advanced technology ZEV cars even if, and most assuredly when, they lose money on them.

Compliance cars put something of a strain on auto makers' communications departments, because the unspoken truth is so, um, unspeakable. So let's divide the B-ED's media debut last week in Silicon Valley into text and subtext. The subtext was regulatory compliance, and of a very expedient variety, too: Rather than rely on in-house R&D, Mercedes essentially contracted with Tesla -- the Silicon Valley car maker and acknowledged leader in electric automobiles -- to provide the EV architecture (motor, transmission, battery, power electronics) for its electron-fired B-Class.

The B-Class ED is the product of a technology-sharing alliance between Tesla and Daimler that goes back to Mercedes' 2009 investment. Tesla will make the B-Class battery pack, power management system and thrashy bits at the factory in Fremont, Calif., and ship them to Germany for final vehicle assembly.

Typically with advanced technology/compliance car projects -- oh, the Honda Fit EV, for example -- the manufacturer will convert an existing vehicle into an EV or plug-in EV, as cost effectively as possible. Then it will make, lease and sell as many units as it takes, at whatever price, to hit the company's compliance targets. Then, God willing, it will shut up about it, because each unit sold loses money. When these cars come up in conversation, auto executives start looking at their shoes.

But, from my tour of California's electric-car culture two weeks ago, I can tell you that is changing. As a class, these vehicles have fully outgrown whatever technical adolescence made them awkward in the first decade of this century. I've driven a gas-powered B-Class in Europe, and the Tesla-powered version is massively better.

One of these days, one of these compliance cars is going to break out, sales-wise. The B-Class ED, which will sell in all 50 states, could be the one. While it might have emerged out of a crass effort at compliance, the B-ED just shines, a completely on-point premium family electric that braids Tesla's and Mercedes' DNA so convincingly the car might as well be called the Model B.

The drive parts are Tesla's devising, including a 28 kwh lithium battery pack and power-management system. An electric motor rated at 132 kW, or 177 horsepower, and 251 pound-feet of torque, drive the front wheels through a single-ratio transmission. That is enough twist to pull the 3,924-pound vehicle to 60 mph in less than 8 seconds, while top speed is limited to 100 mph. Among its curiosities is the car's four levels of regenerative braking, accessed through the steering wheel-mounted paddles. On the most aggressive setting, the car slows crisply when you lift your foot off the accelerator, but it doesn't have the one-pedal operation of its rival, BMW i3.

The B-ED doesn't have supercharging capacity. With a 220V/40A Level 2 charger, it takes 3.5 hours to fully charge a depleted battery, says Mercedes, and 2 hours to raise levels to 60%.

Throughout my 50-mile test drive in the Bay area, the B-ED had great spirit under the spur. And due to its low center of gravity -- the dense battery pack buried in the floor -- the B-ED rides well and corners with a lot more confidence than its gas-powered twin, even though the electric weighs 700 pounds more.

Speaking of weight: The steel-bodied B-ED competes directly with BMW's new and radical, carbon-fiber and plastic-bodied BMW i3. Both are next-generation electric family cars priced in the low $40,000s, and both have roughly the same range, power and comparable performance. And yet the two cars are wildly different, reflecting the industrial strategies behind them. The BMW's advanced-materials approach to weight saving netted them a car weighing a mere 2,860 pounds, fully 1,064 pounds lighter than the B-ED.

The Mercedes' approach is more conservative, fiscally and technically. And we'll have to wait to see the comparative results. These are amazing, uncertain times in appliance sales.