While it may be more accurate, it's a detail that's hidden inside the helmet and won't be seen so it's not a priority for me.
In terms of glueing the halves together I'm thinking the gloss will have a better hold once they're sanded down and have the sanded ABS tab attached. In my experience, having adhered similar haircell textured plastics together, they didn't have as strong a bond as two smooth plastics that have been sanded and stuck together due to the slight uneven texture.
Add in the fact that I'm getting two kits, I'm trying to keep my costs down.