Using this adapter on my Canon M50m2. Auto focus and all settings work just as they should. For $40 this is a very fairly priced piece of kit and is used every day.

I am a portrait/wedding professional, our full time studio does a lot of weddings and that is what we use this flash for. We have a couple Canon 580 flash unites that work great but being a cheep guy I am always looking for something for less. I have a couple of Nissan flash unites dedicated to Canon but have found that they have a terrible auto focus assist lights. With the Nissan there just about useless in dark lighting where the camera can't auto focus itself. With the Sigma EF-610 it is just the opposite, auto focus assist is as good or better then the Canon 580.. Battery usage is very good, accuracy of exposure is also good. Only problem I would note is that you can't see the little diagram that tells you how to put the batteries in very well, especial in low light. I would recommend this flash as a replacement for the Canon 580 at just about half the price. I am going to get another one.

The adapter works as claimed. I've tried it with some Canon lenses I already owned, and the focus is both accurate and reasonably quick.The downside is that the adapter itself adds to the weight and length of any lens attached to it. In many instances this would discourage its use, because it would be difficult to hold it steady. And obviously it could not longer make any pretense toward "pocketability" or unobtrusiveness.

It is pretty helpful to mount any EF lens with my Canon M50 and there is no change in Auto focus and image stabilization which is too good...

This adapter seems to be well made. I haven’t tried the auto focus because I wanted it as an adapter for a manual focus lens. For that purpose it is very good.

I am a learning, amateur photographer. I bought canon EF 2.0X extender because I like to shoot the birds. This extender does not work with my Canon EF400/5.5L USM Len in auto focus. it works with my Canon EF200/ 4L IS USM lens, but slower in auto focus. Its color is good and it produces sharp images.

Disappointing that the auto-focus does not work using a Canon 5D Mark II. I would honestly get much more use out of it if Canon would extend this ability to more of the pro line than just the 1D. Image quality is very good though and it's nice to double the zoom with my existing lenses.

This is a great auto focus lens mount adapter. It seems to work flawlessly the few times that I have used it. I would recommend this product.