I tested this out the same day that I got it and love almost everything about it. Just using it as an extension tubes, with the ability to have full control over your lens function, was worth the price just for that. Then, to be able to reverse mount the lens and still be able to have full control over your lens function, was icing on the cake. The only con so far is, the overly heavy duty cable they used on it. I think if they would had used a more flexible or even a detachable cable, would had made it a perfect unit. I'm attaching 3 photos taken with this. The photo showing the whole top of the lighter was taken with the extension tubes @ 70mm, the other 2 was using the reverse mounting @ 18mm. All 3 was shot with the Tamron 18-270mm lens, on a Canon Rebel T4i body, using auto focus and Aperture Priority settings of f/16.

This piece of camera equipment has become an integral part of my reverse macro photography. It easily takes your kit lens, turns it around to magnify the view and has connectors so that you can still use your automatic focus, ISO, aperture, shutter speed, white balance and more. I would absolutely get this product again!

It does not work with either my Canon 5DsR or 70D. I get a communication error and I can't even take a picture with it in any mode.

The concept is great ---- but it goes into the direction of "good idea, bad execution" .... I tried this with a few of my lenses and noticed after just a few minutes that the cable is getting loose at one of the rings. This will not last long and will eventually break.
The other issue --- and must admit I only "clicked" once I had the Macro rings in my hand - is that the rings are connected by a thread, of unknown dimension. I would have excepted some sort of an adapter for the thread to the Canon Bayonet.

Due to quality issues I'm sending this back

This product attaches solidly to my Canon EOS (5D Mk2) equipment (and other lenses/adapters by aftermarket manufacturers), and functions nicely so far as electrically controlling the lenses. When used with the full-frame 5D sensor (tested with Canon 50mm prime and Sigma 28mm-70mm zoom) , images are clear, sharp, and magnified considerably. So, for strictly Canon equipment this is a great product and I would recommend it.

When using this adapter with other (non-Canon) equipment, there may be some issues. I also tested this with the Sony FS700 (Super 35mm sensor) and Metabones E-Mount to EOS adapter (same lenses as above) I got a very pronounced barrel effect with soft hazy image. This also occurred when mounting the lens backwards (which shortens the base extension length to half) as well. A tighter aperture reduced this effect some. I suspect that the total length of the combined adapters/extensions is too long (about 1- 7/16" for the Neewer + another 1-1/8" for the Metabones) for use with the Sony and 2 EOS lenses I've tried it with. I had much better results with a shorter "dumb" (9/16", no electrical pass-through) extension tube. It may also be the inner shape or reflectivity inside the tube causing a problem with when used with the Sony arrangement, but I think the length is more likely the issue..

Bottom line: for Canon-only uses this is a very useful piece of equipment.