SolidWorks Plastic : Tetrahedral vs Hexahedral mesh

Are you running into problems using tets? My understanding is that a change would only be needed if you were having trouble meshing and that overall they are equivalent. Especially considering you have many other factors such as shell vs solid mesh and the transforms.

Tet-mesh should be fine for most linear work.

Also, explore the difference between H-element and P-element.  P-elements can give better convergence with a coarser mesh, and better results with non-linear materials.

These are geometric elements that represent molecular geometry. The sofware fills the sold model with a mesh based on how these elements best fit inside (fill) your model. Tetrahedral are triangular faces and hexahedral are square faces, Hybrid is the best combination of the two. I select the default "tetrahedral" and the transform default is hybrid. If for some reason hybrid fails it defaults back to tetrahedral.

A hexahedron (plural: hexahedra) is any polyhedron with six faces. A cube, for example, is a regular hexahedron with all its faces square, and three squares ...