I'd go for the solid black. I think the more drastic contrast would look better. I had a solid black canvas top on a Toyota convertible for +4 years (bought it new), and it looked just as good the day I sold it as the day I bought it off the showroom floor. I used a canvas top cleaner and conditioner a couple times a year and kept it clean with regular car wash soap and a microfiber mitt when I cleaned the rest of the car. I'd go for the solid black and not worry about it. I never experienced a single cloth-top convertible horror story. Go for it