This video compares the performance of DigitalRune Physics v1.0 and v1.1. It was recorded on PC (Q6700 @2.66 GHz).
The last heightfield scene was a test with low quality physics settings. - But even with normal quality settings a fully managed .NET/XNA physics engine can simulate a suprising amount of objects. Even the Xbox 360 XNA-build can handle several hundred bodies.
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