I checked out Strange Horizons yesterday for a story I don't have a home for. Every time I think of them as a potential market, I look at their site and end up chickening out because their list of what they don't want includes just about everything.
I'd encourage you to give it a try
if you think your story fits the market, for two reasons.
a) experience in acceptance or rejection (those folks are kind and thorough.) and it doesn't require the cost of a stamp.
b) despite their guidelines, you're never really sure what they're going to like. I had two stories published there a while back, one of them about socks. Socks were the main characters, and it was an omniscient narrator. Go figure.

Editorial detail and suggestions were superb.
Strange Horizons is an on-line stomping ground for new spec-fic authors, as well as established authors. It is highly regarded, pays well, and looks for new talent. Their guidelines are guidelines for a reason - too many ezines end up having to wade through the slush of cliched story lines. Since they are online, and it doesn't cost anything, an author can read their weekly picks (present and past), compare their own work, and have a good idea whether their story matches Strange Horizons' style. If you can immediately illiminate your story, then you've made your job easier. If you cannot immediately illiminate it, it might be worthwhile to send it.