WITHIN THE Lexus R&D centre in Japan resides a team of software engineers that all have brains much larger than my almond-sized CPU.

But that’s not going to stop me from respectfully suggesting there’s room for them to try a little harder.

That’s the core take-out from my four months with the RX450hL. It’s an endearing, mostly pretty polished large SUV that makes the best of unremarkable underpinnings, and is an incredibly easy car to live with.

But … I couldn’t shake the feeling that the hybrid powertrain could deliver both better economy and greater refinement if only the software would allow it to run longer in EV mode. It was a constant minor irk to see two bars (out of five) of battery charge, yet to have the car’s brain calculate that this was insufficient to allow EV operation. Surely there’s predictive software that can use data gathered from recent driving conditions – no extreme hills, no wide-open throttle – to confidently forecast that regenerative, battery-replenishing driving is likely to be imminent? And therefore at least some of that remaining charge could be allocated to the motors?

The niggling sense that the hybrid system is too eager to burn fuel seems backed up by the consumption, which for me, at a least, was unremarkable.

The best I achieved was a low-sevens on a motorway cruise over a few hours with gradient largely in my favour.

That’s pretty good, but throw more typical urban running into the mix – which is where the motors should really be earning their keep – and the fuel burn ratcheted up to mid-10s. Not awful for a large SUV of this size and weight, but well short of the official combined consumption of 6.0L/100km.

The reality for me was that the brief tastes of low-speed EV-only operation were enough to make me realise I’d have bonded far tighter with the RX had it been a plug-in hybrid. Toyota/

Lexus insists that its “self-charging hybrid system” is beaut because you never have to plug it in, and apparently customers think this is a real bonus.

But the flip side is you still have to stop and refuel the thing every 450kms or so, and you only rarely get to enjoy the silky, near-silent benefits that EV-only operation delivers.

Personally, I’d be happier plugging a garage-mounted wall charger into it every second evening or so to avoid the refuelling, and crucially, be able to glide around in EV mode for 90 percent of my driving.

Because in pretty much all other areas of general refinement, the RX is good. The only other thing that could be more polished is the manner in which the V6 kicks into the mix, which can bring a subdued thunk. Otherwise, the suppression of tyre noise, even on coarse-chip, is outstanding, as is the overall soundproofing against wind and ambient noise. Even on the occasion I’d find some try-hard on an unmuffled Harley alongside me, the sense of cabin calm and isolation never diminished, and my normal homicidal urges in these situations remained untriggered.

The RX’s general sense of on-road comportment is nothing remarkable, but it’s competent enough, and the rest of the package is sufficiently persuasive that, despite being in the final few years of its lifecycle, I’d still recommend it make the shortlist if you’re shopping in this segment. But be aware that there’s a few grand to be saved if you don’t need the (tiny) two third-row seats in this ‘L’ variant, and a hefty $11K (and circa 200kg) if you forgo the hybrid powertrain and stick with atmo petrol-V6 power only.

And in considering going down that route, maybe you’d actually be just as satisfied with the 2.0-litre turbo four (powering the front wheels only) in the RX300, available in three equipment grades? On balance, I reckon this is where my money would be going.




Price as tested: $111,070 

This month: 704km @ 10.1/100km 

Overall: 6286km @ 10.5L/100km