I have tried out several programs including Truespace and Shade. But now, my personal one and only is Wings3D. But this very much depends on your own preferences. As for Wings3D: it seems not to have many features but it is very easy to learn and much more powerful than it seems in the beginning. (I have two items in the marketplace and they both were made entirely with Wings3D. Just search for "Kyraia's villa" and "Thobex", if you want to see what this program is capable of).