Can I use AssetBundles with exceptionally large projects?

I'm working on a project that involves a massive content pipeline with tens of thousands of assets which need to be downloaded and released on demand. Only a fraction of a percent will be seen by players at any given time. For my example, just imagine a model viewer. The player needs to be able to view a 3d model, and I have 100,000 models to choose from. I only need to display 10 at any given time.

Unity has its own way of linking dependencies and Assetbundles will work across different types should we need it (scenes, prefabs, animations). So the hope was to use Assetbundles to avoid writing our own export/import when downloading a model/texture/material.

My main problem, is that I recently upgraded to 5.3, and I had to reimport all of the textures/models and it took forever to reimport.

I would like to like to separate the content into it's own project so that the build machine can take care of reimporting the assets if needed? Currently it seems like all assetbundles must live in the same project.

Ultimately all the downloaded content (assetbundles or other format) will be hosted and served up by a CDN, so it would be preferable to separate this revolving content from shipped content like UI.

 

I tried creating AssetBundles in Project 1, but only found 1 file loadable in project 2. I am using the simple tutorial here:
https://unity3d.com/learn/tutorials/topics/scripting/assetbundles-and-assetbundle-manager as a starting point.

 

Means,generally you can not create assetBundles in project A, so they were reliably loadable in project B, can you? Or it is dependable on assetBundle content?
Would that be possible in case of simple content like 3d models or 3d models with some simple GUI elements?
Or did you finally have to use obj importer or something similar for your project above?
Did you get any new findings on that?