I've never used Blender for IMVU. I used it one time to make a Minecraft render so I can't really say which is easier. Personally, I find 3ds Max difficult to mesh in. I don't like the camera controls. However, I have learned how to export a product with it and it's actually not that hard at all. It's annoying at first but once you learn what you need to do it's simple.
Now making the mesh to export on the other hand...
Elie wrote:keep in mind that imvu doesn't support versions beyond 3ds max 2011, 2012 roughly.
There is a beta exporter for 2013 and 2014. You can download it and learn to install it by looking at my 3ds max exporter tutorial:
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