In a world of relentlessly advancing technology, a car that hasn't seen major changes in recent memory might seem hopelessly outdated. In the case of the 2015 Infiniti Q60 convertible, however, there's still some life in the old dog yet. Though it may not sport the latest high-tech nanny features like blind spot and lane departure warning systems, the Q60 convertible still packs a brawny 3.7-liter V6 that demands respect. The graceful exterior styling has also aged well, and the handsome cabin continues to impress with its high-quality leather and available genuine wood trim, not to mention its user-friendly control layout.

As far as performance goes, the Q60 convertible still meets our expectations. When you give the 330-hp V6 engine the crop, 60 mph arrives in well under 6 seconds. Passing power is prodigious at all speeds. The Q60 is also blessed with athletic and engaging handling that's among the segment's best. This convertible certainly earns its sporting credentials.

If you plan to use this Infiniti for more than just weekend joy rides, though, you'll have to factor in the car's practicality or lack thereof. The cramped rear seat and tiny trunk when the top is lowered won't put off true enthusiasts, but more capacious rivals are available if space is a priority. Other drawbacks include the engine's strained sound and feel as redline approaches, and the stiff ride of the IPL model.

You'll find fewer compromises with the 2015 BMW 4 Series, which offers quicker acceleration, a more useful trunk and a roomier rear seat. The 2015 Audi A5 and S5 are also excellent performers and have more top-down trunk space. We'd even suggest checking out the new 2015 Ford Mustang GT. Nonetheless, the 2015 Q60 convertible has enough going for it that it's worth a look in your luxury sport convertible search.

The four-seat 2015 Infiniti Q60 Convertible is offered in three trim levels: the Q60, Q60S 6MT and the performance-oriented Q60 IPL (Infiniti Performance Line). Infiniti also offers a Q60 coupe, which is reviewed separately.

Standard equipment for the entry-level Q60 includes a power-retractable hardtop roof, 18-inch alloy wheels, automatic bi-xenon headlights, heated power-folding mirrors, keyless ignition and entry, dual-zone automatic climate control, leather upholstery, heated eight-way power front seats, cruise control, a tilt-and-telescoping steering wheel, a rearview camera, a 7-inch touchscreen, Bluetooth phone connectivity and a six-speaker sound system with a six-CD changer, satellite radio and an iPod/USB audio interface.

Most options are grouped into packages that require you to add the previous package in order to get the next one on the list. This hierarchical structure starts with the Premium package, which includes rear parking sensors, heated and ventilated front seats, driver memory settings, a power-adjustable steering wheel and a 13-speaker Bose audio system specially designed for use in a convertible. Next up is a Navigation package that adds a navigation system with voice controls and Bluetooth audio connectivity.

Only after you've ponied up for both of the above can you get the Sport package, which includes 19-inch wheels and summer performance tires (available separately), sport-tuned steering, upgraded brakes, unique bodywork and sport seats with power-adjustable bolsters and thigh support for the driver. Last but not least is the Technology package that includes adaptive cruise control, automatic wipers, pre-crash seatbelt tensioning and an upgraded climate control system with an air purifier.

The Q60S 6MT includes the Premium, Navigation and Sport packages as standard, but exchanges the automatic transmission for a six-speed manual. The top IPL trim features similar creature comforts, while pushing the performance envelope with a more powerful engine, sport exhaust, more aggressive suspension tuning, quicker steering, larger brakes, aerodynamic enhancements and unique badging.

Powering the base Q60 and Q60S 6MT models is a 3.7-liter V6 engine rated at 330 hp and 270 pound-feet of torque. The base model comes standard with a seven-speed automatic transmission, while the Q60S 6MT is only offered with a six-speed manual. Rear-wheel drive is standard on all Q60 convertible models.

The EPA's estimated fuel economy comes in at 20 mpg combined (17 city/25 highway) with the automatic transmission and 19 mpg combined (16/24) with the manual. In Edmunds performance testing, a Q60 convertible with the automatic went from zero to 60 mph in a quick 6.0 seconds.

The Q60 IPL convertible uses a modified version of the 3.7-liter V6 that has been tuned to produce 343 hp and 273 lb-ft of torque. The seven-speed automatic is standard. Despite the increase in power, though, don't expect the IPL to be much quicker than the base model. In our testing of various Q60 coupes, the regular and IPL versions turned in identical 0-60 times.

Standard safety features for the Q60 convertible include antilock disc brakes, stability control, traction control, automatically deploying pop-up roll bars, front side airbags, full-length side curtain airbags and active front head restraints. A rearview camera is standard, and rear parking sensors are available. The optional Technology package includes impending frontal collision preparation (pre-crash seatbelt tensioning and brake priming).

In Edmunds brake testing, a Q60 with summer tires came to a stop from 60 mph in 108 feet, a respectably short distance for a luxury convertible fitted with summer tires.

On the road, the 2015 Infiniti Q60 convertible's muscular V6 delivers authoritative acceleration. The seven-speed automatic transmission is an excellent match for this engine, highlighted by its available steering-wheel-mounted paddle shifters and rev-matching function that automatically blips the throttle on downshifts. The manual transmission, on the other hand, is a mixed bag because of the heavy clutch pedal and its abrupt engagement that can take a while to get a feel for.

In the handling department, the Q60 convertible feels well balanced and responsive. The steering is precise, but requires a bit more effort than we'd like, especially with the sport-tuned setup on the Q60S 6MT and IPL trims. The standard suspension provides plenty of athleticism without the harshness of the available sport-tuned suspension, making it a better choice for the majority of buyers.

As automobiles continue to add more features, the interface between man and machine tends to become more complicated. Not so with the 2015 Q60 convertible, which benefits here from its older design. The buttons and knobs for the climate and audio systems are refreshingly straightforward, and the 7-inch touchscreen is similarly user-friendly. Add the navigation system and you get voice controls for all of the above, making your job even easier.

Though the Q60 interior design hasn't changed much over the years, that's not necessarily a negative, as both the styling and materials are top-notch. The standard front seats are both comfortable in straight-line cruising and supportive enough to inspire confidence in spirited driving. The available front sport seats offer additional adjustments that allow you to customize the fit, but unfortunately they're available only with the firmer suspension. The rear seats are so tight that they're really only fit for stowing your personal items.

Oddly enough, the Q60 convertible's trunk is more spacious than that of its coupe sibling at 10.3 cubic feet with the roof up. Lower that lid and it's another story, however, with just 1.9 cubic feet of storage.