To all you who are stuck with large assemblies like me there is a new tool available to help that. CadFaster for SolidWorks is an add-in product that improves the navigation, mating, selections, moving components and other assembly handling stuff. Typically performance is increased 5-10 times.
CadFaster can be downloaded from:You can download full version of the software for free. It will work 90-days without any other limitations. After that you can register it if you want to.
This tool has proven to be usefull in some cases I know. If you are interested, test it!