ANSYS
ICEM CFD BFCart mesh is of a very high quality. A high percentage
of volume cells are near perfect cartesian Hexas.
The above image shows a cut-away subset of an engine manifold. The quality is displayed in three ways.
1) Mesh Color by Quality
2) The Message window shows the number of elements within each range
3) The Histogram chart shows columns in each quality range, it also lists the minimum quality as 0.12. This is good enough for almost any CFD and FEA solver.
Achievable quality is affected by the mesh size and the geometric complexity of the problem. You should expect all the problem elements will be adjacent to the surface. If poor quality hexas are encountered, try the "Create Pyramids" option or the "Split Degenerate" option. You could also relax the projection factor. If there are only a few poor cells, you could solve the problem with Mesh Editing. If the issues are due to near wall proximety, you could reduce the mesh size (it is generally recomended that cartesian methods use a relativly smaller mesh size than a tetra mesh).