RE: wisker bisk with helical vanes?
I just shoot 2 to 4 deg offset so I can't comment on that.
My first problem with it was this weekend at the 3D. My arrow was pushed down into the biscuit and I didn't notice it and shot into the base of a Strutting Tom. I had thought that wouldn't happen. So now I watch for it.
Mine does shoot thunderheads right with the field points out to 30 yds though. Didn't have to mess around to get them there either.
It does a number on my fletches though.