I continue to play with Substance Painter, doing simple projects.
I directly textured my high poly model, but no i rethink it, i should have baked a normal map from high poly to low poly...
I also got several problems : subdivisions artifacts (i need to improve my hard surface modeling skills), shading artifacts that seem to be due to bad UV unwrapping (marking the seams after applying the SubSurf was NOT a good idea ^^).
So, gotta keep working !