![Biggrin user added image](images2/smilies/biggrin.png)
Brian, as always, that's an excellent model. Thanks for poinint it out to me. I always like seeing the progression of your models, though you know that at some point we as a community are going to coerce you into making a tutorial on the proper way to use SubD's.
![Smile user added image](images2/smilies/smile.png)
As for your "should I use photos as textures" issue, I say no. I think it would be different if it were the side of a barn, or a person's face for a game, or some other non-reflective object. But given that a truck/car will always have a reflective paint job (ever seen a non-reflective car? Me neither), having a static reflection on it would just look odd. Any scene you try to put it into would have to be built around making the the lighting work with the photo-reflections. I think it would be so much more realistic to make a shader that realistically provides reflections. Now, you know more about shaders than I do of course, but is it possible to make a shader that has at least two layers - one underneath that has the reflective "paint" on it so that it reflects your HDRI's, and one on top that is just the mud, perhaps with your bump maps to dirty it up? That way the mud doesn't cast reflections, but the underlying paint layer will. I don't know if you can do that, but that's what I personally would recommend.
Cheers.