I'd like to get a flash eventually. And I'd like it if I could have 2 with one as a slave. Money is an issue, but if the Canon is THAT much better, I'll wait and save up. I'm looking at the Canon 580EX (which can be slave and master, right? while the 430ex can only be slave?) or The Sigma EX-500 DG Super. This is the equivalent to the Canon, right? I also saw that there is a EX-530 DG Super, which I'm assuming is even newer if numbers mean anything... Anyone with experience with either? I appreciate your help.