Built to be bomb-proof rather than light, it still works fine for me. Definitely a drawback for air travel. This frame fits the 2.6 Gazz, but not 3.0. Square crown with small slope is knurled for excellent foot grip. Unlike all the frames listed above, this one comes chrome plated, which I prefer.
Paint looks great, but always gets scratched up in the car.
Overall, the chrome and the one-foot capability are two of the strongest points, not to mention that Kris Holm rides one. It's still probably a little heavier than the others, though real strong. Split block bearing holders. No provision for one-footing. I have a MK 5 frame, which I love.