[Palmetto]

1966 Shelby Cobra Convertible (sigh)

No doubt, it would be the best "convertible" of all time, if only it had a top of some kind.

Mazda Miata. Hands down.

[Enduring Freedom]

P O R S C H E
B O X S T E R

[Charles Martel]

You're right, the 427 Cobra did not come with a convertible top as standard equipment. There was one available as an accessory, though.

I'll conceed that the Miata is certainly the most successful drop-top to come along in a long, long time. I think it falls a big short in the "All-time Best" ratings, though - and that may be more due to nostalgia than anything else.

That said, here's my favorite:

1968-1/2 Shelby GT-500 KR, viewed from the angle most familiar to everything else on the road.