I've owned both the Grayling and the Bohning fletching jigs and of the two, the Grayling gave me a little better results.
In fact the Grayling has more positive stops than even the Bitzenburg.
I often use the Grayling for short fletching with results every bit as good as the Bitz. However, I always use the Bitz on 5" feathers. The clamp holds them more firmly.
If you want to save money and don't need to be able to fletch helicals, AAE has a little jig that's about $20.00 that works surprisingly well. It is permently set for slight right wing offset.