The catchlight panel on the 580ex puts glints into eyes when you use the flash in bounce position. The 430ex doesn't have this panel, but it's really quite simple to rememdy the situation. Just take a nice white stiff card, like an index card, cut it to fit the flash head and attach it with a rubber band. I'm sure it will work just as well. No reason why this same white card trick can't be used on other brand flashes, by the way.