Michael !
Its not the library aspect of the componants that
I love its the way you can tell that component to snap
into place that is so cool !!!!!!!
Like you can build a window and move it into a building
you then save as a component how that should snap onto the surface
next time .
It works with arrays too !
You build a model up fast that way too .
A building is set up in a matter of minutes where you need a few hours in others !
Peter