I love this cable, I use it for macro photography as I need to move my flash to the front of my lens in order for it to light up my subject correctly. It works well with high speed sync too with no issues.
My only few complaints:
1. The locking switch that goes onto your camera hot shoe does not actually "lock", but it does stay pretty tightly on the camera so not too big of a deal, but if you were to accidently flipped the locking mechanism (you can easily do that), the connector would fall off and you'd have to put it on again.
2. The cable could be longer, it's a bit short for my taste and the coiling does feel awkward.
3. The fake hot shoe under the part that goes onto the actual flash can't be tightened. It will be hard to use this with a flash bracket as the unit will slip off immediately after being tilted. It however, does have a tripod mounting hole which looks sturdy.
Pros to this product:
1. The cable looks very sturdy and offers some water/dust protection as with the Canon cable.
2. A lot cheaper than the Canon brand cable.
3. Light weight and very easy to carry around.
Over all, if you want to use your flash off the camera hot shoe just for around 2 feet, this is the cable to go. If you need it to go farther, I recommend you buy a wireless system.