Solidworks certainly has its place and I’ve used it for years in the Aerospace industry (work done for Boeing and Airbus). It also has a multitude of tools and built-in features, quite similar to Catia (which I’ve also had the pleasure of using and hate it) and I would say a lot less clunky to use.
Even though the parametrics is great for some things in my mind it is not always helpful. I’ve actually modeled entire buildings in Solidworks:
http://design.medeek.com/plans/planset.pl?action=GARAGE4828-A6D-3&action2=view
A very powerful software package with an insane amount of capabilities.
The model and planset shown above was entirely created with Solidworks, it took me well over two weeks to generate it. Within SketchUp I could generate the exact same solid model probably within a few hours (without plugins).
With my new upcoming wall plugin and my other plugins I can probably generate the bulk of the model within a few minutes.
Solidworks is a great product for a million dollar project that has a project timetable of a a couple of months and a group of engineers working on it. However, it is not so great when you have a small budget, a short timetable, a small staff and you need a lean, mean drawing machine and that is exactly what SketchUp is.