I am currently doing some consulting work for a petroleum company as a geotech. They know that I took arcgis classes in college and assume that i know everything about the software, which I do not. They want to start using Arcgis to make maps with wells (points) and pipelines (lines). I looked through a sheet explaining the difference between the three versions of Arcgis desktop, http://www.esri.com/~/media/Files/Pdfs/library/brochures/pdfs/arcgis1021-desktop-functionality-matrix.pdf I really do not think that the company will need advanced because from what I understand the main difference is that advanced has coverage geoprocessing which I do not think will be needed. Besides making basic maps they want to be able to do coordinate transformations from NAD 27 to WGS 84. I think that would be possible in the basic version but I am not positive. If anyone can provide me with some insight on the topic or give examples of what other oil and gas companies use the software for I would really appreciate it!