City Hunter is one of those anime/manga which could have a great success in the US, with enough ads and marketing. I mean : It's manly, the musics are awesome, Ryo is badass. While the anime may be better know, the manga is better for multiple reasons. The first being that it actually concludes the Arc of Ryo's Past in South/Central America, introducing Shin Kaibara & Mick Angel. There are some great moments of action straight out of Dirty Harry, and the guns tropes are quite accurate, especially in the manga.
But overall it's a great franchise. I live in France, so I had it dubbed over here. But the show was deemed too violent to they censored it quite a bit, especially the villains who were straight out of a Abridged series. I have all manga volumes, all DVD's and movies at home. It says a lot how much I'm a fan.
Favorite characters :
Ryo, Umibozu/Falcon, Makimura, Mick Angel ( And Robert Harrison in the anime. ) Bloody Mary & Sonia Field.