Embarrassingly enough I actually tried that a few times and it didn't work. Textures went missing, models disappeared and the only thing that copied was the lightmap
I did this model of a Jedi Starfighter a while back and decided to make a low poly version. The high res was modeled in LightWave (rendered here in 3D Coat). The retopology is being done in 3D Coat.
Currently, <30 seconds on PS3. That's not including time for lightmap baking etc. for environments. Character assets and single models/props are nearly instant.