After a trip to the foreign adapters I have come to repent at the original. Mechanics, but especially the antireflective coating is much better when Canon mount adapter. This can be seen but only when shooting in extreme backlight. Then there's the third-party adapter quickly once blooming with strong loss of contrast because the enamel lining of the foreign adapter just not as dull and effective as the original. A little tip: if you the lucky owner of the 2.8 / 40mm STM is, you have a very perfect little Tele in combination with the adapter without the M is too top-heavy!
