I personally dislike SketchUp... quite a bit. However, you are free to make use of the program which suites you best. For the record, I've seen several lovely SketchUp models in the past which look as good as anything else produced in a different program. Brother Byron's models are a great example of this.
And, I know what you feel when I read your post. Again, I used to model much in a similar fashion as you. Here's an example of the UXV I was speaking of - the first two images are of the ship with AC3D's two different shader types applied to it, smooth and flat shading:
However, those shaders don't cross over very well unless they're applied with the proper software. Here's the ship when it's either shaded completely flat or completely smooth:
So, is this a bad model? Not really. There's no sloppy geometry, there's no ugly boolean messes lying around that someone didn't bother to clean up, etc. But, the factors which I illustrated in my previous post do apply here. Lighting issues. UV mapping. Subdivsions, if I was nuts enough to ramp up the polycount enough to use it on a mechanical model (not to mention other tricks I'd need to pull to get that to work). So, in many regards, though the model works, the approach is poor and perhaps a bit out-dated. As you can see, he lighting can be fixed manually to an extent, but in general the advice of the prior post is still of great utility.