I have two 400ws monolights. But, I would like to add a third flash and at the same time, would like to be able to use it as a standalone speedlight/off camera flash. I was debating the Canon Speedlight 430 EX II. But I'm pretty sure that the 430 EX does not offer an input for a sync cable... Will a speedlight give me the option of using a sync cable input? or does someone have a different/better suggestion?