I used the Nocturnals. it changed my poi a little bit, but in no way did it cause my arrow to fly funny.
My FOC is already high (16-18 %) so I wasn't worried at all.
My spine is 250, my weight on the front of the arrow is 185 gr, and over all arrow weight is 477 and the arrow length is 28"
My bow is set up to 70 lbs and 28.5" draw length .
I even had some at 14% FOC with only 450 gr total and 165 gr up front and they flew great as well.
My arrows paper tune great and fly straight as can be.
The nocturnals were around 20 gr if I remember right and a standard nock ("F") Is around 6 gr
I have the red ones, blue ones and green ones.
Get the green ones
My red ones were invisible when I was looking for the arrow after my shot, as it went clean thru the elk and was covered in red blood
I love the nocturnal ones, cant speak for any other brand