I have been a photographer for 28 years and have used many products during that time. Like most people, I always strive to get the best bang for my buck. I've been using Canon Speedlites for many years and have had very few problems. Lately I've been wanting to increase the number of flashes used per setup and have looked at the Yongnuo YN568EX. At first sight I was very impressed. All specs seemed accurate and for the price I was sure I'd be happy. This did not happen for two main reasons. To make sure I can't see anything, I ran a test between this flash and my Canon 580EXii. I placed both on stands and used a Yongnuo RF-603 (which I like) as the trigger. I placed them about 15 feet from a large white wall and adjusted them to the same width (24mm) to compare apples to apples. I measured them separately so I could shoot at F8 in the same spot in the middle of the wall. Here is what I found about Yongnuo568EX.1. The light has a very hot center with slow and uneven decay, making it unusable for wide-angle shots or as a flat fill light. Compared to the Canon 580EXii, the light spread was extremely low. If you want to use this light to take pictures of large groups or take pictures of a medium-sized room, you will have a very hot center and dark corners in the picture.2. The color temperature of the light emitted by Youngnuo jumped everywhere. While I don't expect a battery powered flash to be as accurate as my Einsteins, these units had 150 degrees of shift in either direction (a total dispersion of 300 degrees) which, for those who use this flash professionally or for business, just isn't acceptable is those who take multiple shots in the same location and expect the same white balance for each. This flash costs more in post than just buying a Canon flash. I returned this flash after completing this review, but will still be happy to try Yougnuo's next flash. Overall I think they are doing a fantastic job in the transceiver market and hopefully will be able to produce professional quality flashes in the future. Let me know if you found this review helpful.