I finally saw the movie when it came out on DVD. I have to say, I was a little let down, a little disappointed. The story has captured the imaginations of many for centuries, in only oral or written form: it was great enough, on its own, to do that, and did not need all the special effects sprucing up which actually seemed to cheapen it. (Including the grotesques masquerading as the invading horde!)
Also didn't like the fact that Leonidas seemed to be modeled on one or another of America's so-called "Founding Fathers." When I think of that, I want to quote cockroach archy:
you can stuff your bellies with oysters and shrimp you may have your ribbon and bell for bill and me it is liberty o wotthehell bill wotthehell.
-- which is better.
I liked the movie well enough, but not as well as I would have liked to have liked it. ;)
Ok - in any event, I think you two are recognizing the same phenomena but have different reactions to it. 300 is highly stylized, a Frank Miller trademark (watch Sin City or read his Dark Knight graphic novel).
The Ancient Greeks and Romans had a similar fantasist-"orientalist" (if I can use such an anachronism) attitude toward "Asians" ( by which they meant Egyptians,Persians,Parthians,Scythians and the peoples of Asia minor and the Transcaspian region). Miller has simply visualized and exaggerated it.
I'm a big fan of well-made highly stylized movies. For instance, Azumi, which I rank as one of my all-time favorites (although Dan does not rank it so highly!)
Also, I enjoyed Sin City immensely and have watched it several times.
For me, the difference is this: They were meant to be fiction and were based on either a graphic novel or manga (in the case of Azumi) -- are meant from the beginning to be metaphors or fantasies pertaining to imaginary worlds -- whereas 300 is based on an actual spectacular historical event. The mythos of 300 is something I've experienced through other fictionalizations or mentions, particularly Steven Pressfield's Gates of Fire; but it's something I wanted to experience for myself! Ha, an impossibility, but I wanted a connection to the authentic time, people, place, event.
I got a connection to Frank Miller's mind instead.
I suppose my expectations were too great and prefigured my ultimate reaction to the movie. I liked a lot of the slo-mo action, but I missed the authentic culture and people who would have fought there.