I am almost convincing my wife to buy me the Canon flash for this X-mas. Now I am not sure what is really the benefit of Canon SpeedLight 580EX over Canon 430EX. The price difference is about $120 dollars and if the 580EX has great advantage, I am not even going to tell he about the existence of 430EX. Since my ultimate goal is event photography, I would like to have a flash that can be used in different light situation. Also, I am about to take flash crash course in mid-January; therefore, I need to have it as soon as possible. Thank you for invaluable advice as usual.