I downloaded the "West" disc and got 7.93GB. When unzipping the "East" disc, I got 7.61GB from a 3.36GB zip file.
Everything seems alright for me.
I am burning the discs with Mac OS X's Disc Utility now.
Hey, I'm using Mac too. Has anyone had any luck burning with the Mac I kept getting a read error after I burned my disks and put them in the D3.