Wow that's a lot of vertices. VDrift's model format is all triangles, so they'll have to be converted...this shouldn't change the vertex count. It just means each quad will be split in half. I'd say, start with the bug, and first simplify its wheels which look pretty complex. We usually shoot for a low-poly version of our cars first, with around 4K triangle faces, to make sure users with old video cards don't have too much trouble playing. We have thought about also having an option to use high-poly-count models, for users who have super fast machines and don't have any issue displaying them.
Either way the best way to find out how well they perform is to test them out
basically all you have to do is convert all the quads to triangles, and then export the model to JOE format with the Blender export script in our art repository here:
http://svn.vdrift.net/viewvc.py/trunk/to...vdrift-art
The only difference between export and export-all is that you can name all your objects with export-all and it will do it all in one step and name the files for you. You can get by with just export for now. Let us know if you run into problems. If you get a model exported send it along as an attachment on the vdrift-devel mailing list and we'll test it out (or post it on some web space if you have some). Good luck!