This T-Rex was modeled in IZware's Nendo in approximately 8 total hours.
I chose Nendo because it is a great polygon modeler and in my experiences polygons are the best method for animation in 3dsmax. Keeping animation in mind, I modeled it with just enough detail at the joints etc., so that it would animate properly.
When it comes to modeling it's not only about trying, just to make what you want. It is more about making what you want and then being able to do something with it. Using a lower res model will let you morph in real time for instance.
Other methods will suck up system resources when there is no need for detail. After
all the only time detail matters is in the final render. An example would be metaball models. they are quick and easy but very tough to animate because they have no optimization. Nurbs are great and have mapping advantages but In all reality they are basically unanimatble in a production environment using 3dsmax.
Animating a fairly low res polygon control mesh with meshsmooth on top at render time will give you a similar effect to nurbs. Again its not about the modeling method. It is irrelevant how create your model. The issue is what are you going to be able to do with it.
Here is a render of the actaul wireframe that I modeled. There is no smoothing on this mesh, I added all the detail in Nendo using edge connects and cuts.
I'm going to walk away from explaining exactly how I did the modeling on the
Rex. My suggestion would be to goto IZware's site, download the Nendo demo, and do the included Penguin tutorial.
It will show you all the concepts needed. There is no rhyme or reason to using Nendo. You pretty much start with a cube and chop it up a million times and connect a million edges and basically sculpt your object.
It's not really "box modeling" because your not really doing all kinds of extrudes
and bevels. You may do a couple to get the general shape but that's about it. The rest is actually created each of the edges you need to add detail.
A tip when using Nendo with 3dsmax, goto Max3D and download the OBJ importer and OBJ exporter. You want to use these to translate back and forth between Nendo and 3DSMAX.