[xytrix]

Spoiler for Double O's Twin Drive System:

"The two GN Drives installed in the 00 Gundam have been made more compact than those installed in the 1st season Gundams. This is because the stabilizers and other other equipment that regulates the core unit have been made smaller. Perhaps this is thanks to the passage of four years, or it could be technological feedback from the pseudo solar reactors of the GN-X and GN Flag. You may enjoy building this plastic model with this kind of inside information in mind."