*.obj files are Wavefront files, not Lightwave files: Lightwave uses the *.lwo extension for objects.
If you have access to the lwo files, you could use the new Lightwave importer to retain a lot of the original’s information.
As far as your question is concerned: obj is better than 3ds. 3ds has a couple of severe limitations:
3ds only supports triangles, while obj supports quads. That’s enough of a reason for me to avoid 3ds.