Thanks for the reply. I certainly appreciate your having a life -- other obligations trump this wonderful volunteer work you're doing here for the community.
I actually don't think performance, per se, is the issue at all.
It's simply ability to properly work with large addressbooks. I would be more than happy to serve as a test bed to troubleshoot issues, as I'm a software guy. When I tried to use your plug in, only a subset of them came over from Google. I don't use anything fancy--no groups, lists, photos, etc.--so there's something funny going on with both v17 and v24 of TB.
Let me know what I can do to assist in testing/troubleshooting.