I vote black top. The black top just looks better. Even though I have a solid black car, and with apologies to the solid color crowd, solid red looks like a Ferrari wannabe color, and appears more orange on the solid color cars. The earlier red cars appear "redder". Solid white looks too generic, and solid silver is a little dull (my other car is silver with a black convertible top). I really like that 2001 coupe that no one seems to want to buy and that gets passed from dealership to dealership. I don't like the tan interior or the stick, so I wouldn't buy it, but the white with black top looks outstanding.
Having said all that, don't do what I would do. Do what YOU would to do.