I prefer 3DS, a Frog export in 3DS is only 1/10 the size of an OBJ and there's no noticeable difference in quality. The "texture or transmap" problems are about the same for both 3DS and OBJ, both need extra work in VUE, so imho a 2Mb 3DS tree is the better choice compared to importing the same tree in OBJ format at 34Mb.