Bought the one with bulge from A8parts in 2013 or so.
All cars with 110ah battery will be with this bulge since 110ah battery sits higher in a more shallower, but longer battery tray.
I have actually upgraded my car to 110ah battery and changed the battery tray as well. There is a thread on this forum.
When you will find the door cover with bulge you will also need part number 4D0868865GV40, which is essentially part of carpet reinforced with plastic that holds cover at the bottom.
Some pictures not from my car that shows the part:
