the 224 is a must have it works wonders when it comes to blending, nothing can compare in my opinion, the 187 can be used for applying your liquid foundation and it give you an airbrushed looked when u stipple on the product, i also use it to apply my blush since it doesnt pick up a lot of product you can definitely build up the color with this brush. i love the 190 for much thicker foundation since it blends it out real well,