I've used a Yongnuo 565EX for over a year, and just bought two 568EX II's. (I wanted HSS for outdoor work, hence the 568s.) I've used the 565 quite a bit and never had a problem with it. However, the manual is a bit difficult to understand. Just my opinion, but I think Yongnuo makes a decent flash at a decent price. They're not Canon, but good enough for what I do at the moment.