Very good for doing what they are designed for, such as pull-ups, toes to bar, etc. You can also use them for weightlifting bars, but they are not designed for that.

I bought them mainly for exercises on the balance beam. Even with pre-existing injuries, wearing the gloves I could do them without pain. The material is very good, as well as the fit on the hand.

I had finger grips, but after using these, I can't go back to those!
During a program with 100 pull-ups, my palms and fingers thanked me for giving them this gift.
To find the right size for my hand, I found instructions on their website. You measure from the beginning of your palm after the wrist, to the first lock of the middle finger (slightly below the middle of the finger). For me, it was 13.5 centimeters and the instructions said I should get a medium size, and they indeed fit perfectly on my palm.
The table with the measurements and the size to choose is:
Size Measurements (cm)
Small 8-11
Medium 11-14
Large 14-17
Extra Large >17