OverviewTHERE is no need for earth-trembling excavation to uncover why the NX has been a Lexus success.

Within four months a trio of new-generation medium SUV rivals have hit the market – Audi Q5 in July, Volvo XC60 this month, and imminently the BMW X3 – yet Lexus executives do not blink when asked if a facelift of its three-year-old NX is enough to maintain its strong sales performance.

That might be because the NX is thousands of dollars cheaper than those rivals.

It is also about the same price as premium small SUV models such as the Audi Q3 and BMW X1, yet it is hardly pricier than mainstream medium SUV models such as the Mazda CX-5 and Volkswagen Tiguan.

For buyers looking for a premium badge, in-betweener space and an affordable entry ticket, this NX continues to form a unique mainstream-to-premium bridge.

The question is whether this lightly revised Lexus is an overly expensive mainstream, or superbly affordable premium, contender.

Drive impressionsEntry to facelifted Lexus medium SUV ownership now starts at $54,800 plus on-road costs for the NX300 Luxury with a 2.0-litre turbocharged petrol four-cylinder engine, or $57,300 in the case of the NX300h Luxury with its hybrid 2.5-litre petrol four-cylinder and electric motor partnership.

Forget entry to the Q5 ($65,900) or Mercedes-Benz GLC ($67,500), and definitely forget the lofty new X3 ($68,900), because by some margin its nearest premium-badged rival is the $59,900 XC60 D4 Momentum. Yet even opting for the petrol-hybrid Lexus undercuts the diesel Volvo, both of which in combined-cycle conditions sip 5.6 litres per 100 kilometres of their respective fuel type.

So if the Lexus NX300 and NX300h Luxury did not exist, it would suddenly be a huge leap for a buyer to make from a mainstream-badged rival such as the Mazda CX-5 Akera ($49,990) or Volkswagen Tiguan 162TSI Highline ($48,490), and into the above Audi, Bimmer, Benz or Volvo.

With that in mind it is probably best to start at base level what Lexus tags Luxury.

Thankfully there are only a quartet of giveaways that this is an entry model grade: fake leather on the seats that fails to feel premium enough, plus the lack of a sunroof, keyless auto-entry or head-up display. But the latter trio combine with a 14-speaker Mark Levinson audio system as part of a $6000 option package on the Luxury – although suddenly the NX300 is a $60,800 proposition.

Otherwise there are even heated, electrically adjustable front seats, a bright new 10.2-inch colour screen with digital radio and satellite navigation – but sans Apple CarPlay/Android Auto smartphone mirroring – and even active cruise control and auto up/down high-beam included.

On-paper this NX has the game won, though once the option package is added to near-match the equipment of a top-end CX-5 Akera, for example, there is $10,900 separating Mazda and Lexus.

This becomes an issue, because while interior fit-and-finish is high, the materials used do not feel high grade. Rubbery plastic used on the dash-top and doors could be shared with a Toyota Camry, while hard plastics used elsewhere are only occasionally covered with thin, leather-like inserts.

Front seats that are soft and comfortable also lack the firm side support of the F Sport model grades, although all switchgear is laid out logically and even the touchpad for the infotainment system – long a sore point in Lexus products – is easier to use thanks to the widescreen’s extra real estate.

In particular, the 10.2-inch unit (up from 7.0in) allows navigation to remain on one side of the screen and radio stations on a smaller portion, which reduces the need to flick between menus.

Most importantly the NX never feels too small, or too large. In many ways it is perhaps the definition of a ‘right sized’ SUV, and that feeling extends to a roomy but not cavernous rear quarters that is impressively cohesive and complete with air vents, door pockets and a fold-down armrest.

The same description could be used for the boot volume, which at 500 litres these days hovers around the small (X1 is 505L) and medium (X3 is 550L) SUV segments. And a standard electric tailgate is yet another nice touch.

Lexus has firmed suspension bushes and revised its fixed dampers for the NX300 Luxury, and on the road the entry petrol model strikes a reasonable balance between comfort and control. This still is not an SUV for drivers like the Mazda is, but at least the benefit to its around-town firmness is a level ride that avoids the heaving an SUV with a 1700kg kerb weight might be susceptible to.

The highlight of the driving experience is the 175kW/350Nm turbo four-cylinder engine, which sings sweetly and feels energetic in all circumstances.

The six-speed automatic really needs to be flicked from Normal to Sport mode for every drive, however, because in the former setting it is dull and slow to kickdown, while in the latter it is more alert without being aggressive. It improves driveability significantly, without impacting refinement.

At this point the NX300 Luxury is a decent, competent drive. Unfortunately, however, the rest of the range is not so impressive.

The $2500 extra spend to the hybrid powertrain is a backwards step. Not only is it 45kg heavier, but with a 147kW combined output in a 1745kg application, the electric motor must rely too frequently on the thrashy 2.5-litre non-turbo four-cylinder that does not produce its 114kW portion of total power until 5700rpm.

Performance, economy, refinement and driver enjoyment all suffer as a result.

Choose F Sport or Sports Luxury model grades, meanwhile, and Lexus’ revised adaptive variable suspension (AVS) is included as standard. Every NX rolls on the same 18-inch wheel size, but only the F Sport uses lower-profile (55-aspect versus 60-aspect) tyres.

At the national media launch we swapped NX300 Luxury for NX300h Sports Luxury on the same tyre, but found the latter $76,300 flagship model delivered significantly inferior ride compliance and body control.

Indeed the adaptive suspension proved wobbly on even smooth surfaces, porpoising on its axles in Comfort mode. Switch to Sport and control improves but low-speed impact harshness worsens.

Ultimately the hybrid and AVS-equipped NX model grades are way off the pace not merely for the premium segment, but the mainstream class as well. The fact such models are also more expensive only adds to the disappointment.

All of which leaves the entry-level petrol turbo model as by far the best Lexus medium SUV. Even then, however, it feels like a sub-$50,000 offering inside and to drive, though its active safety and infotainment additions should absolutely be commended.

Sadly, a comparison with a CX-5 Akera would not leave the NX shining, while it is hardly a stretch to a new XC60, particularly when comparing Toyota hybrid with efficiency-matching Volvo diesel.

For buyers, that line between mainstream and premium might be an alluring one.

In reality, however, Lexus has more work to do to justify the NX’s ask and positioning.