right helical (or offset)
That's how mine are fletched and I've never had a problem with them in my WB.... I don't know anyone personally that shoots Blazers with straight fletching....
This is right from the Bohning website: "We recommend fletching Blazer vanes with a helical or a 2 to 3 degree offset."
http://www.bohning.com/archery/1049.xml