Re: LED's
What's your budget? What other lighting will be involved? Does color gamut matter to you? I own a bunch of Chauvet SlimPAR pro RGBA fixtures and they hold up pretty well against 575w incandescent fixtures, depending on what you're doing.
Total LED wattage is somewhat indicative, but you need to be careful, as some fixtures embellish specs, just like speakers. If they give a lumens rating, that is a little easier to compare. Many fixtures are rated in "lux at X meter(s)". This is also helpful, but you have to translate the beam and field angles between different fixtures, or you aren't comparing apples and apples. At a bare minimum, you want 1w diodes, and 3w (single color) is probably better. The tri and quad fixtures are potentially fine, but keep in mind that if they have "10w" diodes or something like that, they are adding the emitters behind the lens together, so a 10w quad diode is theoretically 2.5w per color.
Being outdoors isn't really material (unless you're talking about weatherproofing); the facts that are more relevant is your throw distance, how many fixtures you will have, and what are you competing with for other light. You can get fairly good brightness at moderate price ($350 and up), but color gamut, physical features, beam angle and beam quality may require spending somewhat more, depending on how picky you are and what you're trying to do.
