Wear them layered and there is not a huge difference. Wear them alone and there is a difference. I think Sally Hansen DVD wins just because you can get it much easier than OPI DS Royal. I do have to admit that I prefer Royal because of its grapey purple base color.
Nail wheel swatch showing the base color difference.
On the nail over China Glaze Grape Pop.
In low light to show the pink/purple flash.