If you do volume rendering of unstructured grids with ParaView, please tell us which method you use by filling out this poll. If you do not use one of the methods because it is buggy but you would like to use it, please let us know in the comments.
Note, the (I believe) projected tetra volume rendering for unstructured grids transport layer code was extensively rewritten by Utkarsh, and will land in 5.9.0. It has a spectacular performance improvement over 5.8.0. Well done, Kitware!