As an absolute yoga beginner I bought the blocks in addition to a yoga DVD. Now I do not really know my way around with yoga blocks and can not give expert evaluation. However, they seem to me very small in comparison with the used blocks on the DVD. Also there are some (warm-up) exercises where one should stand on the blocks. That's because of the size difficult, in addition, the material is also very much yet, so I find it difficult to find grip.
Overall, not bad for a small price, but I suspect that it is better.