I currently have a 430ex and I was thinking of buying the 580ex and possibly the wireless transmitter if I can get enough money. Would this set up be good for outdoor portraits? I don't have the space in my house to set up a studio so alienbees would be out of the question since I'm going to need them to be battery operated. Is there something else you would recommend instead of adding the 580 to my collection? Also if I just got the off camera shoe cord do you think having my flash 3 feet from the lens would be far enough to the side for most situations when using it as a key?