It’s hard to say “Oh yeah this has red wheat in it” like you can rye, for example. It seems to be a more premium ingredient than white wheat; it just ups the quality in a subtle way that people recognize but can’t quite pinpoint. Briess describes it as “creamy”, and I think that’s true. It just imparts a smoother beer when used in higher quantities. if you’re just adding 5-10% for head you’re probably not going to know the difference.
If a group were to have a blind tasting of a white wheat and red wheat hefe (everything else being equal), I have confidence that people are going to like the red wheat better.
several years back a friend was only able to get red wheat for his hefeweizen brewday. i distinctly recall how remarkable the end product was, and i felt it was his best ever hefe.