This is the second EF/EF-S to EOS M adapter that I've purchased. The first was a similar product but different brand. It was a complete failure. Both adapters cost the same amount, $39 at time of purchase. The Fotodiox arrived the next day. The other brand took nearly 3 weeks to arrive (I think that was a sign). The Fotodiox packaging is nice, it could be given as a gift. The adapter comes with lens and body caps, some competitor adapters do not have caps. No instructions were included, but the assembly of lens to adapter and adapter to body is pretty straight forward. If a person can't figure that out, they likely won't be able to operate the camera. This Fotodiox adapter is 100x better than the other brand I have, NO comparison at all. I shot 50-60 images the first day, not one error using the Fotodiox product. The other brand I could get 8 to 10 photos, then would get an "Err 60" error message - not good. I've tried 3 different lenses with the Fotodiox adapter and all work as they should. The electronic functions work flawlessly with the Fotodiox adapter. Honestly, AF seems faster with the EF lenses than with the native M mount lenses, this may not be reality, but all lenses tested did work very well. The only issue I have encountered is not with the adapter, but with a lens and Canon M50 combination. While using a Sigma 105mm 1:2.8 Macro HSM lens, the lens itself somewhat gets in the way of M50 red lamp AF assist beam. Not a deal breaker as the Sigma lens and Canon still work very well together. This combination really can produce great images. The Fotodiox EF and M mounting flanges are matte finish metal, the casting and machining look good and result in a solid connection of lens to adapter, adapter to body. There is very minimal rotational movement at the lens to adapter, and adapter to body, not enough to cause camera errors, as with the other brand adapter I have. The Fotodiox has approximately 0.5mm of rotational movement = very good. My other adapter has 2.5mm of rotational movement, resulting in continual camera error messages. The body housing looks like metal, but is some sort of plastic, or polymer. It is well made and I don't foresee any issues as the important mating surfaces are metal. Possibly the only negative is the tripod adapter. I have not had an issue, but understand how others claim it is a bit loose, or sloppy when fully tightened. I believe this minor issue can be corrected with the addition of a simple thick paper shim, or very thin metal shim. When the tripod-mount knurled nut is FULLY tightened, there is a little "wiggle". If using large lenses, this minor issue may increase. So, be prepared to either permanently bond the tripod mount to the adapter body, or experiment with a shim to tighten things up. I give it a 5 star overall, even though I only offer 4 stars for Material and Durability. The body housing could have been a metal shell, and the tripod mount issue could be resolved. Neither are deal-breakers. This is a very good adapter. I wish I would have purchased this adapter to begin with.