Petroleum is a very striking and challenging composition. To me it smells like entering a damp cave full of minerals and assorted rotting materials. While all niche brands now put out the requisite oud (and they all end up smelling similar), HdP does something interesting and different with it. It takes the basic oud smell, then amplifies the mineral component, and throws in a big aquatic note. So unique that I had to buy it, but I have not yet been so daring to wear it, in part because I dislike aquatic notes.
But if you can wear it, do so by any means. Longevity is excellent, as with most HdP perfumes. And there's really nothing like it - no cheaper substitutes. Elena at perfumeshrine ( http://perfumeshrine.blogspot.com/ ) has an excellent review, if you search for it.