I tried some .001 arrows both from Tenpoint and some custom made ones from DCA. Did not notice any appreciable difference at all in group sizes out to 50yds. IMO, if you are competition shooting, then perhaps it is worthwhile to spend more money to potentially tighten your groups by an 1/8th of an inch (if you also have the skill necessary to support that) since in that scenario it may make the difference between first place and not placing at all. But for hunting at reasonable ranges, I see no advantage to spending that extra $$$.