For a scan-only workflow, color negative film is usually the safer, more flexible choice. It generally has wider dynamic range and more exposure latitude, so scans can hold more highlight and shadow detail and tolerate over- or underexposure better.

Slide film typically has less latitude, so exposure needs to be more precise. In return, it often gives more saturated color and strong “straight out of the film” look. Some slide films are also low ISO, which can mean finer grain and potentially higher effective resolution in the scan.

So the tradeoff is:

• negative film: easier exposure, more recoverable detail, more forgiving for travel
• slide film: punchier color, but less forgiving

How much the grain/resolution difference matters depends on the quality and resolution of the lab’s scans. If you want convenience and flexibility, choose color negative. If you specifically want vivid color and are confident about exposure, slide film can be a great creative choice.