Hi Hans, thanks for your appreciation. For the first question: absolutely yes, they are strong enough to be used without any problem. For the second question: things are more complex than it may seems (above all, for me, to explain it in english!). Every die of the set is composed by the intersection of a certain number of little spheres (the nodules) with a bigger one (the surface where the numbers go). All the spheres of a single die (the little ones and the bigger) are precisely proportionate with each other to be tangent and inscribed in the same solid (a tetrahedron for the D4, a cube for the D6 and so on). If you change this proportion you'll obtain a non functional die (not well inscribed in his solid, that means unable to lay stable on a plane surface when rolling ends), or, in alternative, you should change the surface where the numbers go in something different from a sphere. Both alternatives are not good, in my opinion, and I wouldn't like to change the D4 design. That said, the correct way to read it is to look wich one of the numbers stands upright when rolling ends (like number 4 in the first pic), while all the others will be leaning on a side.