Four-door sports cars, like motorcycle trikes, have a certain amount of logic to them, even if there's the stench of maturity attached. At a certain point, you can't even contemplate another fall off your Harley Fat Boy. Likewise, you no longer want to wedge into a two-seater that now fits like a half-size-too-small sneaker. It's not necessarily that there's more junk in your trunk; it's more like you just need a trunk.

There's no shame in that. Porsche has taught us as much with the Panamera, its four-door funmobile. Look at the redesigned 2017 Panamera head-on--Inc. tested the 4S model-- and there's no question about the pedigree. Squatty and agile looking, its fat Michelins are searching for some track to eat up. In profile, though, there's no mistaking those extra doors and the sedan length.

Which means that four passengers can experience the Panamera's muscle rather than two. Lucky them. Our 4S tester came equipped with a twin-turboed, 2.9 liter V-6 that dishes 440 horsepower through an eight-speed dual-clutch automatic transmission that Porsche calls the Doppelkupplung. That translates to "reallyfrigginfast," as in 0 to 60 in four ticks. Top speed: just short of 180 mph. OK, maybe that's not the sharpest Porsche in the drawer, but there's more than enough power to win plaudits from your back seat audience. 

And those back seats. You want some room with your zoom? In Inc.'s 4S, the two rear chairs were split by a control console that allows each passenger to adjust her own climate (a $2,000 option). The chairs are adjustable eight ways, and the rear moonroof provides visual relief from the slanting rear roofline. There are a couple of cup holders and, this being a very European car, a cigarette lighter and ashtray. Did we mention the $340 ionizer option?

From the pilot's seat, the view is even better. The Panamera sits low like a sports car, so unfortunately getting in and out is not like getting into your Audi A7, for example. But you're wrapped in comfy black leather ($3,790) in a 14-way power chair with an optional massage package ($1,190). Before you is a glossy black dashboard and center console that, while looking a bit overwhelming when the whole thing lights up, is actually rather straightforward and intuitive. There's much to see: a g-force meter, lap timer, 360-degree cameras, and even an optional night-vision assist camera ($2,540) for when you're prowling the countryside in the wee hours.

The Panamera also lets you tune your drive like it was a radio station. A dial on the steering wheel offers you three settings each for the chassis and pedal response: normal, sport, and sport plus. (You can also set them from the dash.) The sportier you get, the lower the car sits, the faster the response off the pedal. There's even a spoiler that pops up to improve the aerodynamics. So when you want to let this thing loose, it stays well anchored, the all-wheel drive offering admirable stability as the speedometer jumps. Around town, though, you really do want to keep it in normal mode, because this car does not like low speeds. An optional rear-wheel axle can improve the turning radius by offsetting the rear tires' direction 2.8 degrees from that of the front tires.

If you buy a Panamera as opposed to a 911, there's a reason. You need room for passengers and stuff. And when you actually have to haul stuff in this vehicle, the rear seats fold to grant you access to 47.3 cubic feet of cargo space, comparable with a Cadillac Escalade. There's even a station wagon version. And a hybrid version. Want more power? There's a V-8 Turbo model, too, that adds another 110 horses to the mix.

This combination of power, performance, design, and luxury commands attention and dollars. The entry price is $99,900 (because buyers would be put off if it were priced at $100,000 even?). You will not be paying that, because the options are too numerous and too cool to turn down. Our model weighed in at $139,105 with everything from the very necessary adaptive cruise control and safety package ($2,880) to the indulgent sport package ($6,930), which includes a race-tuned rear exhaust system. It's a very grownup Porsche all right.