SketchUp is very easy to use, easy to learn, and very powerful for being a free tool. It's much easier to use than the QUEST CAD world, though the free version of SketchUp has some limitations which make it difficult to get SketchUp models into a format that QUEST will recognize. The free version will only export to the Collada format, which is not supported by QUEST. This means you have to use some intermediary program that can read Collada files and export to something QUEST understands (i.e. VRML 1.0, DXF, OpenFlight Obj).
Until now, the easiest way to get from SketchUp into QUEST was to shell out $495 for a license of SketchUp Pro, which includes a DXF exporter.
I say until now, because luckily the Guitar-List.com website has put together a Ruby plugin for SketchUp that exports from SketchUp to DXF, for free.
That's only half the battle, so with permission from Guitar-List.com I was able to modify their script to use QUEST's built-in DXF to PDB conversion tool so you can automatically export from QUEST to DXF to PDB.
You can download the ruby script here. Download it to your Program Files/Google/Google Sketchup/Plugins folder.
One pre-requisite for this script to work, however, is that you must have your dwg2pdb.bat file configured so that DENEB_PATH is set to whatever your Deneb or Delmia path is. You also must set the DENEB_PROD_DIR to point to the quest folder (default was vmap for me) and make sure LM_LICENSE_FILE is pointing to the right place. These settings should more or less mimic some of the settings from your quest.bat file.
Next copy the dwg_cmd file from your quest folder to the bin folder, and set your default units to inches.
The last thing you'll have to do is edit line 64 of the skp_to_pdb.rb file to point to your dwg2pdb.bat and dwg_cmd files.
It may take a bit of work to get set up, but I've been using it for a few weeks and it's nice to be able to use a modern 3D drawing tool and easily load the geometry in QUEST.
A few notes on usage, make sure you draw to the proper scale in SketchUp, and be mindful of the origin. If your geometry is far from the origin in SketchUp it'll be far from the origin in QUEST, too.
Again if you want to contact me directly just hit me up here or leave a comment.