Sandy,
Do you get those off of Peterhead Breakwater?
Not seen the metalic black version..must do some investigation as I do like a black hook for more "natural" patterns and clear water.
As for the DNA stuff, I went for a white/pearl for the belly/sides of the fly and then beige or chateurse or blue for the back. The pearl and beige makes a stunning sandeel!!!
Its easy stuff to work with and then you just trim to shape with scissors. Tie it in the same you would EP fibre. I was adding a touch of super glue to each bunch as its slippy stuff.
It takes marker pen well so I did a few with "bunker" spots on them. Looks good..well to me anyway
..and you can also add gills with a pen.
The DNA is also good for adding a bit of subtle flash to traditionals such as Deceivers.