RE: Blazer vanes
I also tried the blazers for the first time this year, and am hooked. My broadhead groups have never been better. I was able to consistently get a 3 arrow group with all of the vanes touching from 48 yards. That was with a fixed blade Montec head.
I have mine fletched helical, although I agree that with a vane that short there is not much difference between helical and offset.
The vane should be placed the same distance from the nock that your do for all of your normal fletching, somewhere between 3/4 and 1" from the nock end of the shaft.