Quikspins have to be used in a straight clamp , with slight offset for great results . I used Quikspin ST Hunters for about 12months and found them very accurate , but if you use a whisker biscuit style rest you may have issues tuning .
I use 4" parabolic cut feathers for shooting from a compound bow and longbow , love'm :)

Another alternate vane you might want to consider is the NAP Twister. Similar to the Blazer but doesn't have the little 'tab' that enhances the rotation like the quick spin.
Just another option. I too prefer the 2" Blazer or 4" feathers. For the Blazers I putchased the Bohning 3 degree helical jig designed for them. Works great.