I've experimented with over a half dozen content sliders. The IvyCat slider has become my favorite for its simplicity and fast-loading performance, as well as the optional features, like navigation.
The content can be easily styled with your own CSS. I've even added some responsiveness (which would be a great default feature in a future version).
Most of the content sliders that I see are hugely bloated with too many features included out of the box. IvyCat seems to have hit the mark with just the right mix of features and performance.