Feelthehunt, i've never had alluminum arrows, but thought I'd just chime on on some theory here. It doesn't matter what shaft you choose (2018,1916, GT, AD, CX...) or how it's supposed to shoot out of your bow according to charts and tables. Those are great to help you get to the right area, but only guide lines. If you can get 2018 flying nice and straight with a sharp broadhead, then you're set. One shaft doesn't inherrently pennetrate or shoot better than another. Everyone shoots differently as well. Just get a set up, whatever it is, that flies true and go hunting.