Anyone here have any experience with the Yongnuo 600RT? If so, what are your impressions? Does it seem solidly constructed? I currently have a Canon 430 EXII and a Yongnuo 560II (as well as a couple of older flashes for manual use). I understand that he 600RT will fire either the Canon or the 560 II but will it fire both of them simultaneously? That could simplify my remote flashes for my real estate work greatly.