Jon, I have a good answer: It is faster and easier for dummys like me.
Is gives many good site with models.
I have a workaround for the two problems (3-point spline and many patches).
It looks something complicates, but if you install the programms you became relative good models with 4-point spline.
You need Blender:
MetasequoiaLE R2.3b-2 and Metasequoia Ver2.4.2. You need both, because LE R2.3b-2 has a problem with the import and 2.4.2 with the export.
Install the programs.
If the model has not so many patches, load it in Blender and begin with 7.)
If the model is a dxf- File, load it in MetasequoiaLE R2.3b-2 and begin with 4.)
1.) Load the model in Metasequoia Ver2.4.2 (DoGa CGA System .suf, AutoCAD .dxf, LightWave .lwo, 3D Studio .3DS, Rokkaku daioh .rok, Calgari .cob, Wavefront .obj and Playstation .rsd).
2.) Save it as .mqo
3.) Load it in MetasequoiaLE R2.3b-2
4.) Reduce the polygons. Object/reduce polygons.
5.) Save it as .cob or .dxf (its greater and bake all groups to one)
6.) Load it in Blender. File/Import/TrueSpace or File/Inport/dxf
7.) Select group and go in edit-mode
8.) Select all point. Type A
9.) Remove double vertices. Type space/Edit/Vertices/Remove Doubles
10.) Change the 3-point patches in 4-point pateces. Type space/Edit/Faces/Convert to Quads.
11.) Deselect all. type A
11.) Export as Wavefront. File/Export/Wavefront
12.) Import in AM
The models are not perfect, but you have a model like this
in 5 min.