Cinema 4D. It has its own FlashEx plugin which will export either a model or a complete scene into SWF. Detail can be as high as you want it. You can import any of the usual 3D formats, so you can buy the model and subdivide, texture, animate and export it. You can assign different FlashEx tags to different objects and they can have different line weights and colours. Cinema is, most probably, easiest to learn of all high-end applications. Especially if you want just to import and export stuff from it. The core version which already has the plugin is not terribly expensive, around 600 euros, pounds or dollars, depending on where you buy it.

-- erlik