I personally would recommend 3D Studio Max r3. But of the two you mention, probably Lightspace. My vote for that is due to the fact that Lightspace has been used in several TV and movie productions, whereas Truespace has, to my knowledge never been used, and is a user's nightmare as far as user friendliness and GUI. None of them are easy, the learning curve is very steep on all of them. You might also consider Softimage. And, if you want real bang for the buck, download Strata 3D for free, then buy the accessory packs to bring it up to full functioning. But I still say 3DS is the best overall, if you can't afford Maya, and who can.

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