I have only started designing 3D models a few month back (July 2011). So there might be problems with some of the models. However, I would not set the status to "for sale" if I have not tested them. So, for most of the models for sale, you will see a photograph of them.
However, even if I find a model working, there might be some slight changes in the model for sale. I will state that in the description.
If you want to buy several items of the same part or want me to put different models into one file, send me a message and I'll try to create that file for you.
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