Not that I'm about to do a blender node tutorial, but the blender node is superior. If the tattoo is at a high resolution (don't know -- haven't gotten my newsletter yet), then you can scale it down in the material room, position it, etc. and have it applied via the blender node. This can give effectively give you the tattoo at a much higher resolution than the underlying skin texture due to the scaling. That's important if you're doing a closeup.