In my experience the biamp stuff isn't nearly as stable. The software is still pretty buggy.

It also has a limitation/feature. When you design a system using multiple boxes it automatically decides which DSP unit does the processing for each element. This theoreticlly makes programming easier but if one box fails you might lose your whole system. With soundweb you have proper distributed processing so if one box or the network fails, everything else keeps working.

There are ways of 'forcing' the DSP layout but why bother?

Audia is also much more expensive. Especially now the new non-networked Soundwebs are available for the smaller setups.