I was not sure if the files are fully supported for all 3D Softwares as advertised. For the moment all was OK! worked! it was easy payment, 3D Models World is a great place (better deals than other websites) I wish they will add more 3D Models.
The biggest fear was that the model is not very detailed and far from the real crane. But when I open the model using an AutoCAD I found that the model was very very detailed even I can directly use it for an FEM simulation in other commercial software. 3D Models World could help you a lot in your projects.
I was not sure that whether I would get a 3D model or a kind of software to build up the model, I got timely responses to my question . Also very nice models with a wide variety and at reasonable prices.