G2 frames have a head angle somewhere around 69°. A non-G2 frame will have a head angle ~71°. The higher the head angle, the faster the steering. This makes the G2 frames inherently slower/floppier handling. They correct this by increasing the fork offset which increases the trail and makes the handling faster and less floppy. Another added benefit is that toe overlap becomes less of an issue.
Also, the wheelbase gets extended and rider weight moves more towards the rear. Depending on your type of riding this could be an advantage or disadvantage.