Do you think the extra features of the 580 are worth having for the additional cost compared to the 430 EX
For bridal pics I use a 550ex and two 430s. They work extremely well together, highlighter, fill-light, whatever. The 550ex on-camera and bounced off-ceiling controls the other two. You get studio-like control and FEL gives you good metering. For multi-flash setups I believe you need either a 550ex or a 580ex.