RE: Offset fletching vs. straight?
Tune with straight and shoot with as much offset or helical as your set-up will allow.
Especially if you' re going to use fixed BH' s, you' ll have to ' select' your best arrows for that purpose.
I used 5" straight fletch feathers on Beman Hunters for years with fantastic results. Now that I use a MZE, I take advantage of the drag characteristics of full helical.