This question comes up ALL the time (and I just answered it in another thread), so I thought I'd post my video here to help you choose between the canon 270EX, 430EX II and 580 EX II flashes:
"Choosing the Best Canon Flash for Your Needs"
I've been accused of being too hard on the little 270EX in this video, so in its defense let me add: -- the 270EX can be a good choice if you are shooting with one of the pocket-sized Canon cameras that has a hot-shoe, like the G10, G11, G12, etc. or if you are using a pro SLR that lacks a pop-up flash and you want a tiny little on-board fill flash. Otherwise I still recommend the larger flashes.
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