The same gradient out of Photoshop at 300 - 400 ppi @ 100% will be an un-necessarily large and cumbersome file. Screen ( monitor ) rendering in InDesign may or may not give you an accurate rendering of the actual vector gradient in InDesign or Illustrator. You should have your InDesign view set for high quality and the document resolution set for 5080dpi / 300ppi ( depending on RIP screening requirements ). Monitors tend to have an issue with rendering gradients accurately. Proof the project to check the rendering via a reliable printer ( i.e., Postscript Level 3 RIP ). But, getting back to your original question, gradients in Illustrator are different than Photoshop gradients whereas IL = Vector; PS = Bitmap. However, the RIP will render them the same through its internal print engine. How the gradient is created will make or break the artwork.
