Good idea, Philip.
I hadn't tried that. The settings were "Shaded with hidden edges" and the three topmost effects checked. I now tried without ground shadow, and with wireframe only. Can still get the lag to be visible in a small (from scratch, 5 objects) material.
The way it feels is like when one is typing something, and the things get "lost" in a keyboard buffer. Of course, with a 3D mouse this renders 🙂 everything pretty unmanageable.
Please say if there's anything I can do to help you debug this. I have available: Mac Mini 2009 (2GHz, 4GB) OS X / Windows 7 and Macbook Air Core i7 (4GB) OS X.
Might try on Windows next - earlier 3DConnexion's drivers used to be way more optimized there (unfortunately - their fault, not yours). Maybe you can *pressure* them? >;)
Asko Kauppi
IT guy into Cleantech.