Hey everyone,
I'm currently looking at purchasing myself a flash, I Currently own a Canon 600D and my mate suggested the 580 EX II, He let me borrow it over the weekend so I could take some photo's of a friends birthday party 21st, the flash did a really good job!
I've looked on the interwebs and the going price for a 580 EX II is around $580~ though a Yongnuo flash is around $180 from an Australian seller.. I've heard they both do similar things though you can't use the Yonguno as a master flash for slaves but I don't need to so no problem there.. even if I was to use the whole master / slave setup I would definitely go for the 580 EX II and use the Yonguno as a slave so it isn't a waste of money.
I would be using the flash to take portrait shots / event photo's / weddings and pretty much everything in general when needed.
I'm looking at these guys http://www.fotogenic.com.au/Flash_Studio_Kit_with_Wireless_T…
as they offer a 1yr warranty on it, I'd rarther spend the extra $ as I've seen on youtube and google repair videos for this particular flash from time to time..
The YN565EX seems to get pretty good reviews. Seems a lot better built than the previous YN models too.
Another option IMO would be the Nissin Di866 II. It's got some nifty features like an additional fill in flash when bouncing.
TBH though, if you're looking into getting seriously into photography (i.e. weddings and event's like you said), you may as well just save up and get a 580EX II in the first place. 580EX II's are a bit cheaper now too, thanks to the 600EX-RT's availability now. Not to mention if you ever want to sell it, it won't lose as much % value as a Yongnuo flash. Better to have peace of mind and a reliable flash with better refresh rate and weather sealing if you're going to trust yourself with weddings IMHO.