Oh yeas, Stefan.
With Maxwell or Cycles (or Thea Render) you can undoubtedly get best renders with higher quality.
But...you know I'm always at the constant search of the fastest workflow possible and considering that i really hate all the tedious retopo/UV map stages, long times ago I discovered that when i simply need super-quick concept renderings one of the best way is to use internal PBR shaders of 3D-Coat along with its voxels.
This allows me to completely jump the retopo/UV map stage and focus all the energy only on modelling phase and the creation of the quick (but also acceptably good) renderings.
For that scenario I do as follow:
1) Create the 3D models with any 3D tool (my preferred clearly are Moi and 3D-Coat, and sometimes Blender)
2) Export the model in ply or obj with very high poly count
3) Import into 3D-Coat and Voxelize
4) Eventually, only if I need to apply more materials on the same model, i procede to slice up and separate my model into individual pieces
5) Finally I apply simply PBR Shader to the hi-res voxels
6) I do quick render using the builtin PBR renderer of Procreate.
Very good result (for concept renderings) at a minimal fraction of the times needed if I should use the "legacy" model-retopo-uv-texturing phases.
P.S.
Lately I purchased the excellent material Collection for Blender from
https://www.cyclesmaterialvault.com/
Most of that materials works very well also WITHOUT retopo/UV!!
So now I have also another option when I want to create very quick concept renderings.