So i'm writing my mesh system and some of the file formats keep track of rather a face is just a triangle or quad. Understanding that even the GL_Quad uses triangles in the background. I'm thinking that you will only have 4 vertex calls compared to 6 for the same effect. Though it could be faster, but i hear glBegin is costly. SO i'm thinking 2 phrase, GL_Triangle and a GL_Quad with only 2 begins per mesh might be worth the extra work?