I paint with solvent paints; once and then I throw it away... how much solvent and detergent will it cost me to clean them for the next time?

They are thin and do not hold much color. They also lose some bristles easily. It is good to wash them with water at the beginning to remove any loose bristles.

However, for their price, they are good. They are particularly convenient for applications where either the material is difficult to wash or the brush will not be needed again, as their price is cheap and you can simply throw them away when you finish.

Good value for money. You do your job and throw it away. You get 10 and have stock for many household tasks