Inspired by the British roadsters of some four decades ago, the Mazda MX-5 Miata roadster has won over legions of driving enthusiasts since its introduction in 1990. But unlike those cantankerous English sports cars, the Miata offers Japanese reliability and build quality. Prized for its go-kart-like handling, quick-dropping top and timeless styling, the Miata has earned widespread critical acclaim and overwhelming consumer interest.

Over the years, the Mazda Miata has received a steady stream of improvements, including a stiffer chassis, more power, a larger interior, a glass rear window and more aggressive styling. Last year, Mazda gave its pint-sized roadster a full redesign. Now representing the car's third generation, it's roomier and more powerful, but still as fun as it ever was.

The major news for the 2007 Mazda Miata is the addition of a power-retractable hardtop (PRHT) version. Unlike the two previous Miata generations and their optional removable hardtops, the '07 features an in-vehicle, power-operated retractable hardtop similar in concept to the tops on cars like the Mercedes-Benz SLK or Lexus SC 430. The Miata's top is a three-piece design. When activated, the top breaks into two pieces that quickly drop into the well. The motion is similar to that of the regular soft top. The third piece is a tonneau cover that lifts up to allow the top to drop into the well, then lowers back down.

With the PRHT, it's a win-win situation. When you want an open car, it's just as good as the traditional soft top, and when you want a closed car, it's vastly superior. One might expect a hefty weight penalty, which would hurt the Miata's light-on-its-feet nature, but no worries there. The PRHT weighs a mere 70 pounds more than the ragtop.

Regardless of which version you lean toward, the ultra-nimble 2007 Mazda Miata is a fine choice for an affordable roadster. General Motors' twins, the Pontiac Solstice and Saturn Sky, are the closest things there are to consider against the Miata. Although they possesses sexier styling and available turbocharged engines, neither can touch the Miata when it comes to overall refinement. Drive the Miata and GM twins back to back and it will quickly be apparent that the Miata feels more communicative, eager and responsive.

The 2007 Mazda Miata lineup consists of four trims: SV, Sport, Touring and Grand Touring. Geared toward racing enthusiasts, the SV (only available in soft-top form) offers a black vinyl convertible top, 16-inch alloy wheels, a CD player and power windows and mirrors. The Sport adds air-conditioning and a leather-wrapped steering wheel. Touring model additions include 17-inch alloy wheels, a strut tower brace, cruise control, keyless entry, six-speaker audio (versus four) and steering wheel-mounted audio controls. The Grand Touring trim boasts a black or parchment cloth convertible top, leather-upholstered and heated seats, a seven-speaker Bose audio system and silver interior accents. Retractable hardtop models are offered in the top three trims and are identical in equipment except for the substitution of the power retracting steel top for the soft top.

A number of packages allow further personalization. The Convenience package (available for the Sport) provides keyless entry/power locks, cruise control, foglamps, "global open" which is one button that lowers both windows at a touch, steering-wheel-mounted audio controls and covered storage cubbies behind the seats. The Suspension package (optional on the Touring and Grand Touring) features a sport-tuned suspension, Bilstein shocks and a limited-slip differential. An interior trim package offers aluminum cabin accents, while the Appearance package adds a front airdam and lower-body skirting. A pair of Premium packages is offered on the Grand Touring: Number 1 (not available with automatic transmission) adds stability control, a limited-slip differential, advanced keyless entry and xenon HID headlights. Number 2 is the same, minus the limited-slip dif. Stand-alone options include run-flat tires, satellite radio and a rear spoiler.

The Miata's 2.0-liter, inline four-cylinder engine makes 166 horsepower (163 with automatic transmission) and 140 pound-feet of torque. A five-speed manual transmission drives the rear wheels on SV and Sport trims, while the Touring and Grand Touring trims upgrade to a six-speed manual. A six-speed automatic with paddle shifters is optional on all but the SV and the Sport retractable hardtop. Acceleration is brisk -- we've timed a six-speed manual Miata at 7.5 seconds for the 0-60-mph dash.

Antilock four-wheel disc brakes are standard, as are side airbags. Stability control is also available, but only as an option on the Grand Touring model. A tire-pressure monitor is available on the two top trims and comes standard if the run-flat tires are ordered.

The Miata's inline-4 pulls willingly and revs freely. It's a delightful instrument to play, especially with a manual gearbox. Although tuned for a smoother ride than before, the 2007 Mazda Miata still changes direction like a roller skate and speaks to you clearly through the steering wheel and driver seat. With a lowered top and an open road, Mazda's roadster has few equals when it comes to sheer entertainment.

Although bigger than its previous generations, the latest Miata's cockpit remains a snug fit. Still, it is comfortable enough for two on a weekend getaway. If you pack light, the 5.3-cubic-foot trunk can accommodate a few days' worth of luggage. Although simple in design, the cockpit offers richer furnishings than before, along with more storage. The manual top can be raised or lowered from the driver seat in a matter of seconds. Offering the quietness and security of a coupe, the power retractable hardtop can transform itself into a roadster in just 12 seconds.