having played the NAA, NFAA and olympic outdoor games where it was a MUST to fletch with plastic vanes from flex-fletch to spin wings in order to achieve as fast and low and stable an arrow flight from 40 yards out to 100 meters, but none of those vanes were as significantly consist for me and hunting and good ol' turkey or goose feathers, for stabilizing large surface broadheads. fletchings, like 99% of all trad bow tackle, is as subjective as they come. whatever works best for ya, will be best ... that is, unless there's the issue of misuse.
i'll add ... the main reason i want really large feathers on a hunting shaft is to straighten out its flight as quickly as possible, for that short 5 to 25 yard trip to the critter i'm hunting. this isn't target archery, with its regimented stance and form. this is about drawing anchor where yer lower body form can take many different positions, all of which can affect arrow flight. i long ago found that those "critical" arrows, that put more of a demand on form and release, just can't cut it when out hunting ... particularly at venues and in conditions that the target boys don't play in.