||August 22, 2009 11:01
This may be a little off topic because it doesn't address charltonjames' original question about getting geometry out of SketchUp (very limited options unless you use the Pro version or get a plugin).
You questioned whether quality is lost with IGES. That's a relative term. Relative to STL and other faceted formats (where the geometry is represented discretely) you will gain quality with IGES since it retains the analytic definition of the object. It's also relative because your receiving software may do things with the faceted geometry in an IGES file to "smooth" it, but you have to wonder how much a smoothed faceted geometry differs from the original representation.
Perhaps the idea of losing quality when exporting to IGES is due to the IGES format's notoriety as a "bad" file format that some receiving systems have a hard time reading. The main reason that IGES files are "bad" is because people don't write the file correctly. IGES is a standard and implementers of IGES exporters often violate the standard (i.e. write the data in unique and unexpected ways). Therefore, a receiving system isn't looking for non-standard data and hilarity ensues.
Sometimes I feel that I'm too defensive on behalf of IGES.