@peg_T - What genre? What do you mean by “enhances”?
Typically when people are talking about a harmonica mic, they’re talking about adding some dirt or grit, which you typically wouldn’t want on a vocal unless you’re going for a Jack White kinda vibe.
For a clean sound on both, I did a review of the Beyeredynamic m160 which I LOVE for clean harmonica and works well for vocals as well (I’ll post a link at the bottom of this post) but I’m pretty sure you’re not wanting to shell out $800!!! 
But if that’s the sort of thing that you’re wanting, then you might consider the Audix Fireball microphone. Hope that helps!