It's been more than three years since I last checked out BMW's quirky little electric i3. Beneath its goofy exterior design, the i3 is still a technological marvel, fitting an electric powertrain inside an advanced carbon fiber chassis and a gorgeous cabin made of sustainable materials. I continue to be impressed by this weird little ride.

But there's something new this year. The model gains a new sporty "s" trim level that builds upon the efficient, electric performance with slight spec improvements to power and agility. It's now slightly quicker, slightly sportier and a lot more fun when driven with spirit. But how does that jibe with the i3's eco mission?

Widening the wagon wheels

The BMW i3 has been notorious for its weirdly tall and narrow tires. The standard model corners, accelerates and stops surprisingly well on its Bridgestone Ecopia EP500 155/70R19 -- that's like temporary spare narrow -- tires' unconventionally shaped contact patches.

The i3s still rolls on Bridgestone Ecopias, but steps up to wider 175-millimeter rubber up front and 195-mm wide contact patches for the rear wheels. This improves overall grip when cornering. The new rubber is wrapped around larger 20-inch wheels with shorter, stiffer sidewalls and hangs from a firmer suspension for improved responsiveness and agility.

This is still pretty narrow rolling stock -- even the very un-sporty Prius Touring rolls on much wider 215s -- but the BMW is still surprisingly nimble. However, the grippier i3s tends to follow roadway ruts more aggressively than the standard model, so it requires more vigilance to stay straight at highway speeds.

A tad more power

The i3s steps the rear-drive e-motor's output up to 181 horsepower and 199 pound-feet of torque, a boost of 11 horsepower and 3 pound-feet over the standard model. That's a modest performance boost that, realistically, you'd be hard-pressed to notice from the driver's seat.

Like the standard model (and most electric cars in this class), the i3s feels very responsive at city speeds due to the way its e-motor delivers max torque from zero RPM. With just a single reduction gear, there's no shifting to deal with, just uninterrupted thrust all the way up to its terminal velocity.

The 0-60 mph sprint is reduced from 7.2 seconds to 6.8 for the more powerful i3s EV. That said, the additional weight of the optional range extender brings it right back down to 7.6 seconds, so it seems you can either have more performance or more range, but not both. Top speed is raised from 93 to 99 mph, though you probably don't want to spend too much time there. It's hell on your range.

Regenerative braking recaptures kinetic energy as electricity when coasting or decelerating. The system is so aggressive that it's possible to drive the car mostly with just one foot; lift the accelerator and the car immediately begins to slow. It takes getting used to, but I dig this driving technique.

The i3 features a few drive modes to help drivers customize their performance-economy balance. i3s drivers will, no doubt, be interested in the Sport mode which amps up accelerator sensitivity during dynamic driving. Eco Pro mode dulls down throttle response in pursuit of maximum range, while the most aggressive Eco Pro+ setting goes a step further by shutting down the climate control system and soft-limiting the top speed to 56 mph.

Cruising range

With a light foot, the standard i3 gets up to 114 miles of driving range per charge from its battery pack, according to the EPA's reckoning. The meatier tires on the i3s trade rolling resistance for its grip, which brings the estimated cruising range down to just 107 miles.

Recharging time is the same for the i3 and i3s: the 94-Ah (33-kWh) lithium-ion battery pack charges in about 5 hours at a 220-volt Level 2 charging station. In a pinch, you could use the included trickle cable to charge from any 110-volt wall outlet, but that'd take about 20 hours.

The fastest way to charge, however, is at a 50-kW DC charging station, which allows an 80 percent quick-charge in just 45-ish minutes.

My i3s is equipped with the optional gasoline range extender. This two-cylinder gasoline generator kicks in when the battery is depleted, adding about 70 miles of range and bringing the total cruising distance to about 180 miles.

The range extender is not at all physically connected to the powertrain -- it's basically a tiny, loud, portable generator with a 2.3-gallon tank -- and it barely produces enough juice to keep the i3 rolling. There is a noticeable drop in power when you pushed into the i3s' extended range. It'll have you heading straight for the nearest DC charger.

Proper trip planning, standard DC fast charging and urban-centric performance envelope likely eliminates the need for the range extender for most potential i3 buyers. I'd save the money and skip this $3,850 "upgrade."

Sustainable cabin

It's a little goofy-looking on the outside. The i3 wraps the BMW i8's futuristic plastic and carbon aesthetic around the silhouette of a stubby hatchback. The compact features a four-door design, though the rears are half, reverse-hinged doors that can't be opened independently of the fronts.

The i3's dumpy silhouette makes way for a surprisingly large cabin within its small footprint. The upright windshield, pushed far forward, and tall roof give the front row an airy feel. Thin profile front seats and a dipping window beltline make even the second row feel more spacious.

Not just spacious, the i3's cabin is also surprisingly gorgeous. The dashboard's shape is both visually interesting and functional with smart storage cubbies and shelves built right in.

The i3 comes in four trim levels -- Deka World, Mega World ($1,400), Giga World ($1,800) and Tera World ($2,600) -- with increasingly high-quality cabin materials. The Giga World is the sweet spot in the lineup with the best mix of real Eucalyptus wood veneer, fabric and leather, metal accents and panels composed of renewable and sustainable plant fibers and recycled plastic.

Sufficient tech

Ahead of the driver is a small LCD screen that serves as the digital instrument cluster. Front and center, a second display floats over the dashboard: home to the iDrive infotainment suite.

I have a love-hate relationship with iDrive. On one hand, I dig the interface and the iDrive controller. I find them easy to use and understand for most onboard functions. The onboard maps look great and the connected features make it easy to find charging stations on the go and monitor the vehicle remotely.

On the other hand, many rarely accessed features can be tricky to access in the deeper reaches of the menus. Also, I'm constantly annoyed by the lack of Android Auto and inconsistent Bluetooth connectivity, which makes listening to my preferred media sources awkward. Even Apple CarPlay connectivity, which is optional, can be clunky to set up and activate.

Driver aid tech

Advanced driver aid technology is not the i3's strong suit. There's a standard rear camera, rear "Park Distance Control" proximity sensors and that's about it.

A $2,500 Technology Package upgrade adds adaptive cruise control that maintains a set following distance behind a lead car even in stop-and-go traffic, but there's no lane departure warning, no steering assist tech, not even blind-spot monitoring. Aside from the adaptive cruise, this is a very basic highway setup.

The rear proximity sensors can be upgraded to front and rear as part of a $750 option. An extra $200 adds automatic parking steering assist, which is a nice touch.

The i3's driver aid suite is a mixed bag. If you're looking for a more modern mix of high tech driver aid features, take a close look at the new Nissan Leaf… or maybe get in line for a Model 3.

A pricey showpiece

The 2018 BMW i3 starts at $44,450 for the base model before a $955 destination charge, but also before any EV incentives you may qualify for. The sportier i3s climbs to $47,650 but, personally, I don't think the modest performance gains are worth compromising the already limited range. Stick with the standard model.

While you're at it, skip the optional range extender. The i3 isn't really built for long hauls one way or the other and the standard DC rapid charger is a better solution for range anxiety.

Grab the Giga World interior trim, metallic paint ($550), the Technology and parking assistance packages, and add destination to come to a sweet spot price of $51,245.

The i3 is a technological marvel, and a pricey one at that. You're not just paying for an electric car; you're also paying for the advanced carbon fiber and aluminum chassis -- there's no production car like it -- and the sustainably designed cabin. For some, this innovation, craftsmanship and technology is worth its hefty price tag.

But I also can't confidently recommend the i3 because it's so expensive. Chevrolet's Bolt, for example, is a much better value coming in fully loaded with nearly twice the range and better tech for just $43,905. No, the Chevy isn't anywhere near the eco-chic premium showpiece that the i3 is, but it's a much better car and, really, a better value.