When I import standard 3ds files I usualy delete the clusters and the textures. But if you want the textures to come in with your models, that won't help you much. Unless the texturing is very complex, I would do it over. Since most of those models were created with 10 year old software, (probably 8+ years ago.) I suspect that most of the texturing is very simple anyway. Redoing it in XSI would be easy and your best bet.