Excerpt: It does what it does. I purchased two of these and I will use one in a speaker with a micoSD (TF) slot and possibly the other with an old Raspberry Pi. Good quality, but as my headline indicates being class 4 minimizes some of the practical uses of these due to speed.
Summary: It works fine for me. With my Android Zinger ZTE, its a complicated process just to move apps and data to the card, but I don't know if other phones have the same complaint. It's not as simple as "drag and drop" as so much else is now days.