BMW's pumped-up, pint-sized Z4 Coupe has won the first battle in its war against a gaggle of compact German coupe competitors by hitting Aussie shores narrowly ahead of Audi's sexy new TT and an entry-level Cayman from Porsche.

Technically all three models are hatchbacks, but that won't stop BMW claiming the M version of its Z4 Roadster-based hard-top is a “pocket GT” that aims directly at the top of a high-performance coupe market that also includes the Munich maker’s own M3.

BMW openly admits its top-shelf Z4 M Coupe, which is claimed to be among the stiffest models it has ever produced, can lap Germany’s famed Nurburgring quicker than the current M3, with which it shares its glorious 3.2-litre straight six.

Offering 252kW at a frenetic 7900rpm (more than Ford’s turbocharged 4.0-litre six) and 365Nm at 4900rpm, the latest iteration of BMW six-cylinder M engine was introduced way back in the E46 M3 of May 2001, and also powers the Z4 M Roadster launched here as part of an upgraded Z4 convertible range in April this year. It returns claimed (EU) average fuel consumption of 12.1L/100km and emits 292g/km of CO2 emissions.

When BMW’s next-generation M3 – to be based on the redesigned E92 3 Series coupe also released in October, led by the twin-turbo 335i - adopts V8 firepower from late 2007, both Z4 M models will live on as faithful recipients of the finest (and final) six-cylinder from BMW’s M-division skunkworks.

Until then, short of the V10-powered M6 (0-100km/h in 4.6 seconds) coupe, the hardtop Z4-M is BMW’s quickest coupe, officially blasting to 100km/h in five seconds dead – the same time BMW claims for the Z4 M Roadster, which weighs 10kg less at 1410kg, and two-tenths quicker than the E46 M3.

While the M6 coupe enters Porsche 911 territory by lapping the Nordschleife in around eight minutes, the Z4 M Coupe isn’t far behind at 8:15. While that’s marginally quicker than the M3, crucially, it’s also five seconds better than a standard Porsche Cayman S, the M Coupe’s closest rival, can manage.

Priced at $127,200, the six-speed manual-only M Coupe is priced almost $10,000 lower than its (pre-GST) predecessor and the last two-seater BMW tin-top, the five-speed Z3 M Coupe. It’s also $21,300 cheaper than the 1340kg Cayman S manual ($148,500), which is powered by a 217kW/340Nm 3.4-litre flat six and also comes as a five-speed auto ($153,100).

The Z4 3.0si Coupe, which shares its super-light 195kW/315Nm 3.0-litre magnesium-alloy six with the Z4 3.0si Roadster, is priced at $87,900 for the (same Getrag) six-speed manual and $90,500 for the six-speed ZF-sourced auto with paddle-shifters.

The 3.0-litre offers 0-100km/h sprinting in a claimed 5.7 seconds (six for the auto), weighs 1320kg (auto: 1350kg), returns claimed average fuel consumption of 8.9L/100km (auto: 9.0L/100km) and produces official CO2 emissions of 213g/km (auto: 216g/km).

It lines up closest with this month’s new base Cayman, powered by a 180kW/273Nm 2.7-litre boxer six and priced at $118,000 (six-speed manual) and $122,600 (five-speed auto). Porsche claims 6.1 seconds for the 2.7 manual.

Next month’s new Audi TT coupe range will be topped by the 184kW 3.2-litre DSG quattro ($88,900), which hits the national highway limit in 5.7 seconds, while the 147kW 2.0-litre TFSI front-drive manual does it in 6.4 seconds and will open the 2+2-seater TT’s account at $68,900 (auto: $72,500).

Similarly, Alfa Romeo’s manual-only Brera coupe opens with (136kW 2.2-litre) four-cylinder power from $69,990, alongside the 191kW 3.2-litre V6 AWD flagship ($94,950), while further down the price scale Peugeot’s 407 Coupe spans $65,990 (V6 manual) to $72,500 (HDI auto) and Nissan’s 350Z coupe ranges between $62,990 and $67,990.

Meantime, over at arch-rival Mercedes-Benz, the folding hard-top SLK two-seater opens its (auto-only) account at $88,400 for the 120kW/240Nm 1.8-litre supercharged four-cylinder SLK200K, and includes the 170kW/300Nm 3.0-litre V6 SLK280 ($101,400), the 200kW/350Nm 3.5-litre V6 SLK350 ($114,400) and the 265kW/510Nm 5.4-litre supercharged V8 SLK55 AMG ($163,400).

The four-seater CLK coupe range echoes the SLK’s engine line-up but starts $3000 lower at $85,100 for the CLK200K, while the 285kW/530Nm 5.5-litre V8 CLK500 costs a Cayman S-like $149,100 and AMG’s ballistic new 354kW/630Nm 6.2-litre V8 powers the recently upgraded CLK63, which costs 911 money at $199,900.

Just as the twin-seat Cayman is based on Porsche’s second-generation Boxster convertible, so too does the two-pew M Coupe sprout from the Z3-replacing Z4 Roadster launched here in July 2003 – but the obvious difference is Porsche charges a $16,000 premium while BMW offers a discount.

Approved for production in December 2004, the Z4 Coupe features the same long-bonnet, short-overhang profile as the roadster, along with BMW design chief Chris Bangle’s controversial "flame surfacing" design language, which debuted on the new 7 Series five years ago and has since extended to 1, 3, 5 and 6 Series models.

Opting for a fixed, rather than folding, roof (BMW’s first flip-top lid will appear on next year’s 3 Series convertible) has resulted in one of the stiffest coupes around. Though reluctant to compare body rigidity figures with claims made by other makers, BMW says the Z4 coupe’s torsional stiffness is 32,000Nm/degree.

When Cayman was launched, Porsche claimed that at 31,500Nm/degree its body "set new torsional rigidity benchmarks for the sports coupe segment" by being almost as stiff as the 911 coupe (33,000Nm/degree). Like Boxster and even the 911 cabrio, the Z4 Roadster is not nearly as rigid at 14,500Nm/degree.

Mounted ahead of the rear axle and behind the driver, Cayman’s engine is genuinely mid-mounted, but with its inline six positioned behind the front axle, technically the Z4 Coupe is mid-engined too. In any case, BMW claims an optimum 50/50 weight distribution and says the fixed roof allows a stiffer suspension set-up than the roadster’s.

Beneath the sweeping roofline and wide-opening rear hatch is a retractable blind and 340 litres of boot space (300 litres in the conventionally-tyred Z4-M, whose boot space is robbed by the M Mobility kit’s compressor, etc). That’s significantly less than the 410 litres of total cargo space offered by Cayman, which comprises an under-bonnet compartment. Cayman is also far slipperier than Z4 Coupe, which in M form offers 0.35Cd aerodynamic drag co-efficient.

While there’s no 2.5-litre version, the 3.0si Coupe features the same electric power steering system as its Z4 Roadster donor car, along with staggered (8.0-inch front, 8.5-inch rear) 18-inch alloys with 225/40 front and 255/35-section run-flat tyres.

Standard 3.0si safety equipment includes front and side airbags, ABS anti-skid brakes, DSC stability control, brake-force display, brake pad wear indicator and seatbelt pretensioners and force-limiters. Also standard are rain-sensing wipers, front foglights, remote central locking, power windows/mirrors, climate-control, trip computer, a 10-speaker sound system with six-CD changer, cruise control, multi-function steering wheel, aluminium interior trim and power/heated/memory sports seats trimmed in Oregon leather. Woodgrain trim is a no-cost option.

Echoing the Z4 M Roadster, the M Coupe switches from run-flat tyres to conventional rubber and, even more significantly, from electric to hydraulic power steering. BMW says run-flat tyres don’t offer speed or load rating demanded by the M car, and that conventional power steering is better suited to its higher performance. The latter offers just 2.4 turns lock to lock and a 10.5-metre turning circle (3.0si: 3.0, 9.8).

Visually, the M car adds quad exhaust outlets, more aggressive bumpers without front parking lights, an alloy bonnet with highlight creases and half-inch wider (9.0-inch) rear wheels with higher-profile (225/45 front and 255/40 rear) tyres.

Further more, apart from its award-winning engine, there’s a variable M differential lock and braking hardware and lightweight suspension components from the track-targeted M3 CSL. The M car’s wheelbase is 2mm longer than the 3.0si at 2497mm.

A heated/folding wing mirror package ($450) is the only option for the fully loaded Z4 M Coupe, which comes standard with a swag of features that cost extra for 3.0si buyers. They include M Sport suspension ($870), M Sport seats ($1550), rear parking sensors ($920), bi-Xenon headlights with washers ($1820), alarm ($760), satellite-navigation with TV and monitor ($5700 BMW’s "Radio Navigation System" is also available on the 3.0si at $2500), Bluetooth preparation ($500), voice recognition ($900), an M sport steering wheel ($375), the superb THX-certified BMW Professional HiFi system ($600) and, believe it or not, metallic paint ($1175). BMW’s SMG transmission and iDrive systems controller are not available.

Exclusive Z4 M Coupe paint colours include Imola Red, Interlagos Blue and Sepang Bronze.

BMW Group Australia plans to deliver 100 Z4 Coupes by year’s end, including 55 M Coupes, plus a further 200 examples in 2007, when the new coupe could almost double Z4 sales for BMW.