Be sure to read all 37 reviews (4 pages) that are found on that website you posted.
Their are complaints that the flash will not work with some Canon and Nikon cameras.
Several complaints that the flash unit was DOA (Dead on Arrival).
Sounds like - "you spends your money and you takes your chances".
..
what do flashes like these
http://www.amazon.com/Neewer-TT520-Speedlite-Digital-Cameras/dp/B004KV4DNK/ref=sr_1_3?ie=UTF8&qid=1327280273&sr=8-3 lack from the canon and nikon brand flash?

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