Top designers pick 10 best convertible designs of all-time

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The beach. Barbecues. Family get-togethers. All things "summer." And what better way to enjoy the good weather than in a convertible! Dropping the top and hitting the road is a summer "must-do."

To celebrate the season, we asked some of the auto industry's top designers to chime in with their favorite convertibles of all-time:

•Walter de Silva—head of group design, Volkswagen AG
•Ralph Gilles—president and CEO, SRT brand and motorsports and senior vice president, product design, Chrysler Group LLC
•J Mays—group vice president, design and chief creative officer, Ford Motor
•Adrian van Hooydonk—head of design, BMW Group
•Ed Welburn—GM vice president, global design

What follows are the cars that at least two of these designers think should make our all-time best convertible design list. Be sure to read all the way to the end to discover their full lists.
(Unless otherwise noted, "Original MSRP" is sourced from NADAGuides.com. "Current value" is based on Hagerty.com values as of April 2013.)

Alfa Romeo Duetto Spider
Selected by: de Silva, Gilles, Mays, van Hooydonk
Original MSRP: $3,950 (1967 model)
Average current value: $23,288 (1967 model)

This Italian beauty is one of the two convertibles that made four out of our five designers' lists. It's also a pop culture icon, appearing in the 1967 Mike Nichols' classic, "The Graduate." And just as Mrs. Robinson (Anne Bancroft) tried to seduce Ben Braddock (Dustin Hoffman) in the film, the Alfa seduced our all-star design panel. Gilles notes a "fantastically elegant rounded tail that made the vehicle appear even lower and sleeker in the rear view," while van Hooydonk adds "not many words required: simply [Italian design firm] Pininfarina's masterpiece for Alfa." And deSilva calls the car "very romantic." Coo, coo ca-choo Duetto Spider.

Jaguar XKE/E-Type
Selected by: de Silva, Gilles, Mays, van Hooydonk
Original MSRP: $5,595 (1962 model)
Average current value: $80,407 (1962 E-type SI model)

The same four designers who picked the Alfa Romeo Spider also are in agreement about this '60s-era cat (1961 model pictured). They're in some pretty good company. As the story goes, when Enzo Ferrari (yes, as in "that" Ferrari) first saw the Jaguar he said it was the most beautiful automobile he had ever seen. De Silva and van Hooydonk love the "long bonnet." Gilles adds his "heart skips a beat when I see one in person." And how many cars can brag about being in a world-class art museum's collection? Mays notes that an E-type Jag is "a permanent exhibit at the New York Museum of Modern Art—kind of says it all, doesn't it?"

Ferrari Convertibles
Selected by: Gilles, Mays, van Hooyndonk
Ferrari 250 GT Spider California LWB
Original MSRP: $14,000 (1958 model)
Average current value: $4,677,050 (1958 closed headlight model)

Ferrari 250 GT Spider California SWB
Original MSRP: $13,600 (1960 model)
Average current value: $7,665,500 (1960 closed headlight model)

Ferrari 275 GTB/4 NART Spider
Original MSRP: N/A
Average current value: $8,555,500 (1967 model)

A trio of ultra-rare Ferraris make our list. Ford's Mays says his favorite is the California LWB (long wheelbase), built from 1958-1960, one of which sold for a staggering $11.3 million dollars at a Gooding auction in August 2012. No slouch either is the SWB (short wheelbase—pictured here), which replaced the LWB in 1960—one of which brought more than $8 million at an RM Auction in January. Chrysler's Gilles is won over by the SWB's "incredible proportions with its long hood… and a wonderful tapering belt line that marries beautifully into the rear fender." BMW's Van Hooydonk's choice is the NART Spider, "one of the prettiest of all open-top Ferraris." Only 10 were made and American Ferrari dealer Luigi Chinetti personally asked Enzo Ferrari for the thumbs up to build the car for his North American Racing Team (NART). The NART also had a starring role in the original "The Thomas Crown Affair" with Steve McQueen (no stranger to fast cars) and Faye Dunaway. For all these Italian beauties, we simply say: Grazie!