Optically the ZEISS FL is tough to beat for brightness and sharpness. I've heard that they have a special prism that allows for less light loss than Swaro or Leica and that gives them the edge in brightness. Pretty cool to hear that one has a definite unique feature that the other two don't have, while all of them say "we have the best lenses and our coatings are the greatest, yada yada yada."
Leica makes really good stuff, too, but you gotta get the two in your hands and see which one feels/looks the best to you. Line 'em up side by side, spend some time looking through them outside, and do what you want to do - not what advertisements or buddies tell you to do. Everyone has their own set of criteria for choosing optics so go with your gut after you test them out.
Good luck!
