svdl,
when I export a .3ds from Sketchup and bring it into V5i,
I exported a 1000' cube
it came in as 12000 vue units... so... you are correct.  But this then is too big to work with in VUE.  I typically work with large models, on the 1/4 to 1/2 mile or more in size... gets KINDA big if 1 unit = 1 inch.

I have started to try to rescale my objects so that 1 VUE unit = 1 foot.... this seems to be better for VUE to handle... but then I have to scale down most stuff by 1/12 or multiply by .08... for some plants to come in at correct scale, but most plants and people or content comes in at all diff. scales for some reason.