We use Otsuka's Mercury for indoor painting, but in simple cases (such as where you do not have to worry about finish or sticky water paint) use this. Including and spitting is good. It can also be disposable (Mercury can not). It is recommended not to use this brush, but to wash before use. The hair loss also decreases, the feeling of use changes. In the case of water, the inside of the brush will be moistened and spit out will be smoother (after washing, wipe off moisture, but the inside is moist). Although it is a good product, there is no rating as good as the same DX oiliness.
I like it because my back is strong and hair loss is small. It is suitable for painting outer walls and roofs with convex and concave surfaces. Because the price is cheap, we use it at disposal for each site.