Use mesh collider on a lowpoly model instead of multiple boxcolliders?

Hello! I'm working on a game which targets mobile devices, currently for Iphone 4 and better. I'm currently working on a lowpoly missile which has 38 tris. I wonder if its better to use mesh collider for this shape or apply more or less 10 box colliders to fill the shape (as it has a pentagonal shape). How much diffrence is it in performance, maybe nothing to think about? Best regards