Override vs. Create Custom Class

Which is better?

[Miki]

In terms of performance, load times and efficiency, is it better to create custom classes or to override the default styling of existing HTML tag?

[aevea]

In terms of performance and load times, I don't think it matters whether you style a class or a tag. But in terms of code bloat, it's usually better to style tags and multiple selectors than classes.

Adam