My exposure to niche stuff is far more limited than a lot of other posters, but I've sampled quite a bit from a few of the houses.
You just can't wrong with Creed Aventus. I hate to be that guy, as it pops up in seemingly every thread. But it's just true. It's unique and women love it.
Dior Homme Intense is a good option that isn't niche, although kind hard to get your hands on outside of the internet.