Macbook 2012 SSD and internal reader

There is indeed a wide variety of opinions on this card. I have read some reviews and decided to try it just once, because I was afraid that most dissatisfied users have the wrong requirements.
The card is fast, in fact, but only if the periphery is around it accordingly.
My setup is a Macbook Pro Retina 2012 internal card reader and an internal SSD.
I get 56 MB / s read and 85 MB / s read speed.
With a Sandisk ImageMate All-In-One USB 3.0 Reader I get 56 MB / s read and 83 MB / s read speed.

Why are so many people unhappy?
The card will not provide the data given when one of the following things arrives:
- Your card reader is not over USB 3.0 connected (USB 2.0 and FireWire 400/800 are bringing max 20-30 MB / s)
- Your internal memory is a hard drive (unless it is very, very fast)
- Your card reader is Tchibo, Hama, etc. (or worse)

Incidentally, the cameras are least able to support the writing speed.
I can not say anything about the long-term performance, should I be unhappy here, there is a supplement if necessary.