Could you elaborate on the spline technique? I've read about it in Blender forums, how do you use it most effectively? Looks great!
Since Im a beginner, I wont be detailed. There should be a good amount of tutorials on the net, including this very forum. It is very simple. Just draw splines on more important lines of the car, using BPs and photos, together with camera/perspective match and artistic skills. For example
Bezier corner in 3ds max is probably best for drawing because there aren't many points like ordinary non smooth polyline, and curvature is easily controlled. Bezier corner is good for sharp edges, too.
https://www.artstation.com/artwork/LAd1v
After drawing spline cage, create surfaces with lofting, boundary or modifiers, on 3 or 4 sided spline cage parts.
After that details can be added to body. Because NURBS aren't usable for non-static objects, conversion to polies is highly recommendable.
Same algorithm can be said for interiors, but they are harder because of asymmerty and rare blueprints are usually very limited, so using photos is basically far more important.
Blender 2.79 had limited support and flexibility for NURBS and splines. I don't know if 2.8 changed that. Blender is still very simple and intuitive for poly modelling. Matching models to photos is also good.
I probably will never abandon poly modelling, because IMO it feels less risky and easier to edit. But NURBS make better surfaces quicker and especially for modern cars that is important. They can be converted to polies to be more usable too. As for NURBS vs. polies I came to conclusion, after using both as a beginner and reading the net, that they are equally good IMHO, but in very different ways.
EDIT explained a bit more on lines.
