There are 2 models in archive - model with materials and PBR model. They are absolutely identical, just one model is a baked version of another.
Model with materials is more usable for the applications such as car configurator, where you can change all details colour, roughness etc. It uses plenty of materials and textures.
PBR model is more suitable for game engines/realtime web applications and use:Car paint material - not use textures (use simple colour), fully unwrapped and ready to be paint if needed.Glass material - not use tuxtures, fully unwrapped.Exterior material - 4k texture set (metallic workflow)Interior material - 4k texture set (metallic workflow)Engine material - 4k texture set (metallic workflow)Wheel and suspension - 4K texture set (metallic workflow)
Model created in Blender 2.79b, so will worrk in versions 2.79b and later.