I picked up House of Flying Daggers yesterday and popped it in with the Wife last night. It's an eye-popper, that's for sure. Hero (also by HoFD director Zhang Yimou) impressed me greatly with its stunning use of color in its costumes, but the scenery was mostly bleak (appropriately for the story, I think). In HoFD, the scenery is as lush as the remarkable wardrobe.
The scale is different, too. While Hero featured wide shots of vast armies, HoFD is much more intimate. Attackers number in the dozens at most and the outdoor landscape is mostly dense forrest, contrasted with the vast desert of the other film.
Getting past the visuals, HoFD also has a fantastic story.
If you have any fondness for Hero or Crouching Tiger, Hidden Dragon, House of Flying Daggers is highly recommended.