@denji: In my case (1) it doesn't misfire when I'm using a manual focus only lens (no electronic circuits), (2) it misfires sometimes when using an original Canon lens, and (3) it misfires most often using a 3rd party lens. Either we got lemons or this is really expected from 3rd party flashes. I don't think I'd be able to sell this na so wala nako nag-up ani na post. If I do decide to go the strobist route, magamit pa man guro as a tertiary flash.