Is 64 bit system beneficial?

I've considered purchasing a 64 bit XP workstation and havethe following questions.
1) Is 64 bit SolidWorks as stable as 32 bit?
2) Will it speed working with large assemblies?
3) Will it help run CosmosMotion? I currently get insufficientmemory crashes.
4) Any comments on the Dell Precision 690?

I also welcome any generic comments/suggestions regarding the useof 64-bit SolidWorks.

-RyanSolidworksAdministration