Hilleberg GT Tents

From almost all Hilleberg tent models there are also GT-version available. So what's the difference between normal version and GT-version?

Hilleberg GT Tents have extended vestibule, GT versions are especially good choices for dog mushers and cycle tourers because the extra large vestibule allows plenty of storage space for sled or bike equipment. In fact, you can park two bicycles in the biggest GT’s vestibules!