Infiniti’s QX50 premium SUV is completely new for 2019, with a strikingly good-looking exterior, the first production variable compression ratio engine, new driver-assistance technology, and a handsome interior with oodles of space for five passengers, cargo, and whatnot.

Infiniti refers to the QX50 as midsize but the EPA puts it in the compact category, as does most of the information you’ll see about it online. Infiniti isn’t trying to pull a fast one here. The 2019 QX50 does give the visual impression of a midsizer and the roomy cabin reinforces it. But I’m not going to take sides against the EPA because, who knows, maybe it’s a felony. My team of lawyers isn’t very big, and not one of them specializes in fuel economy issues.

About the QX50’s new engine: It’s a 2.0-liter turbocharged four-cylinder, and the world’s first production-ready variable compression ratio engine. Don’t expect me to explain how it works. Not that I understand it myself. It’s complicated. Just know that it’s one of the most advanced internal combustion engines ever produced, and it increases the QX50’s front-wheel-drive fuel efficiency by 35 percent, and all-wheel-drive by 30 percent, over the car’s previous V6 engine. Even so, output is higher than many other turbo engines: 268 horsepower and 280 pound-feet of torque.

The engine’s driving partner is a continuously variable automatic transmission (CVT).

Fuel economy ratings for the QX50 are 24/31/27 mpg with front-wheel drive, and 24/30/26 mpg with all-wheel drive. Premium fuel is recommended.

There are three trim levels: Pure, Luxe, and Essential. Base pricing for front-drive models with a $995 destination charge included is $37,645 for the Pure; $40,495 for the Luxe; and $44,445 for the Essential. For all-wheel drive, add $2,000.

I tested the Essential trim with all-wheel drive and nearly $13,000 in options including Sensory, Autograph, ProAssist and ProActive packages.

The Essential trim without options is nicely equipped, but a truly premium experience just about requires the Sensory package ($7,500) that adds heated and cooled front seats, power tilt and telescoping steering wheel with heat, natural maple wood interior trim, 20-inch wheels, and a 16-speaker Bose Performance Series audio system.

The Autograph package, in case you were wondering, includes white leather diamond-quilted seats and blue ultrasuede interior accents. Ultrasuede, in case you’re not sure, is a synthetic fiber that looks and feels just like actual suede but doesn’t involve animal cruelty.

The QX50’s Achilles heel is its infotainment system, which is less intuitive and more distracting to use than it ought to be. As an unapologetic tech shamee, I liked that it included a CD player, but couldn’t believe that the display showed only the track numbers, not the song titles. It has something to do with metadata, whatever that is.

During the test week two friends and I went to Roslyn on a twofold mission: To celebrate one’s birthday (she had never been to that quaint little town in the Cascades where “Northern Exposure” was filmed), and to view an exhibit of the other one’s daughter’s artwork.

Though the CVT made itself a little too obvious a few times, the QX50 tackled the climb up and over Snoqualmie Pass with much grace and no struggle. We were all talking constantly because that’s what women are legally required to do. It was amazing (and I don’t throw “amazing” around carelessly like some people) how we could carry on our conversations without ever raising our voices. The QX50’s cabin is insulated against all outside noise.

The atmosphere inside the car was further enhanced by the supreme comfort of the seats.

In a separate situation while I was driving with enthusiasm on a Snohomish County backroad, a rabbit jumped right in front of me with approximately no time to avoid a fatality. The QX50 did a nosedive when I jammed on the brakes, but the car stopped instantly and one little cottontail’s life was spared.

2019 INFINITI QX50 ESSENTIAL AWD

Base price, including destination charge: $46,445

Price as driven: $59,085

Mary Lowry is an independent automotive writer who lives in Snohomish County. She is a member of the Motor Press Guild, and a member and past president of the Northwest Automotive Press Association. Vehicles are provided by the manufacturers as a one-week loan for review purposes only. In no way do the manufacturers control the content of the reviews.