RE: Grayling Jig/ Arrow length
As far as the Grayling jig, I have one and it works great. I didn't drop a ton of money and it has flethed hundreds of arrows with no sign of malfuctioning.
As for the length of your arrow. I tend to like mine about 1/2" away from my rest. I know some people like 1" and some like it in front of the shelf. Really it is just a personal call.