Cool idea, but how much can they really improve accuracy? With a Hooter Shooter and a standard nock you can pound the arrow into the same hole over and over. It doesn't get much more accurate than that.
How much they can really improve accuracy depends on how well you've got your standard nocks fitted to the string. Nocks that fit right? They do really well, and these nocks probably won't improve anything. Nocks that are too tight really screw up accuracy and cut arrow speed. I'm sure these things would do wonders for that kind of situation.