But driver criticism that the 2.0-litre, straight-six 24-valve rear-wheel drive saloon lagged behind the sportiest models from rivals such as BMW and Audi in power has prompted Lexus to introduce a 3.0-litre version of the car.
The same engine will also feature in the IS300 SportCross, a lifestyle estate with a boot little larger than some upper-medium hatchbacks, although Lexus claims target customers are not looking for full estate capability, but will instead favour a distinctive exterior design.
From a fleet perspective the extra litre in engine capacity inflates the list price of the IS300 saloon to £26,700 (from £21,205 for the IS200 Sport, decreases fuel consumption to 25.9mpg (from 28.2 for the IS200 automatic) and pushes carbon dioxide emissions to the point where company car drivers will face a benefit charge of 33% of P11D value under next year's CO2-based tax system for the IS300, and 35% for the £28,450 on-the-road IS300 SportCross.
For tax conscious fleet drivers, Lexus points out that the IS300 undercuts the list price of its key 3.0-litre German rivals, and comes as standard with features and luxuries that still have a price tag attached to them on Audi, BMW and Mercedes-Benz options lists, such as full leather seat trim, CD-autochanger, cruise control, automatic transmission, curtain airbags and 17-inch alloy wheels.
On spec-for-spec analysis, the Lexus emerges a clear winner. The IS300 saloon's £26,700 price tag includes almost every gadget and luxury item you will ever need. By comparison, key saloon rivals such as the Jaguar X-type 3.0 V6 SE costs £5,150 more once the options list has been raided to match the Lexus. A similar spec-for-spec exercise sees £6,077 added to the Mercedes-Benz C320 Elegance, £8,115 added to the Audi A4 3.0 quattro SE and £5,970 added to its key rival, BMW's 330i SE.
All this adds up to tax savings for the Lexus driver when the new emissions-based company car tax system comes into effect in April.
Sales volumes for the car are relatively modest, suggesting a vehicle designed to cast a halo effect over the rest of the Lexus range, rather than drive crowds through dealers, with the manufacturer planning to sell about 400 IS300 and SportCross cars this year, and 1,400 next year.
From a service and maintenance perspective the 3.0-litre engine is well tried and tested, the IS300 having been on sale in the United States since mid-2000.
It arrives with 20,000-mile service intervals (with midway oil changes), and costly key parts should not require replacement during a standard working fleet life. The timing belt, for example, is scheduled for replacement at 100,000 miles, while the spark plugs should last 60,000 miles.
This longevity is all part of a Lexus initiative for dealers to treat their aftersales operations as customer service points rather than profit centres, with profit to be delivered through new and used car sales.
And with Lexus basking in the glory of overall first place in the JD Power customer satisfaction survey, fleets should have the added peace of mind that they ought not to have to call on the car's three year manufacturer warranty.
WHEN the first pictures of the SportCross landed on my desk, I was not very impressed with what I saw. The addition of the 'estate' body at the back made the svelte IS look ungainly.
But in the flesh the SportCross is far better. From the C-pillar forwards, the car is pure IS saloon, which means chunky looks and a nice power buldge in the bonnet. Behind the C-pillar, Lexus has added a large tailgate and a pair of quarterlight windows, while retaining the distinctive light clusters from the saloon.
Behind the wheel, both models are identical to the smaller IS200, bar one giveaway feature: the automatic gearbox and steering wheel-mounted E-shift gear buttons.
This feature allows you to play at being a Touring Car driver, although the buttons (two at the front for downshifts, two at the back of the wheel for upshifts) are confusing and I would prefer a button on the left for downchanges and one on the right for changing up. Using the E-shift means sliding the gearstick from conventional, fully automatic Drive mode into the manual position. Then all you do is press the buttons on the steering wheel to change gear.
In fully automatic mode the IS300 offers seamless gearchanges and smooth performance. But using E-shift livens up proceedings a fair bit - the engine is much more eager to rev up to the red-line. On the hilly, twisty roads we drove on the model's launch in Switzerland, the E-shift mode proved its worth.
Diving hard on the brakes for yet another hairpin, you simply fingered the button and the engine blipped the throttle to downshift.
Handling in the SportCross has been barely affected by the added weight (50kg), which means a keen set-up for enthusiastic drivers.
The 3.0-litre engine certainly provides plenty of go, but it somehow isn't the huge leap forward over the IS200 I was expecting. I ran a long-term IS200 in manual trim and found it offered more than enough go for daily driving.
I'm sure a manual gearbox allied to the 3.0-litre engine would provide a more distinct performance gap. Lexus is trying to get a manual version for the UK, but this depends on production volumes and demand from elsewhere.
If your drivers aren't too bothered about their monthly BIK bills, the SportCross would be a fine choice. Personally, I'll wait a bit and see if Lexus decides to introduce a 2.0-litre SportCross for the UK - that would be an ideal car.