Unfortunately, when the character leaves the TOPS - his weapons aren't returned, so they CAN'T demo the amazing types of weapons!!!!!
The commentator recommends that the demo guy "fire up a quick save" in order to get access the "disappearing" weapons.
Just too funny.
(If you don't want to watch the whole vid, the relevant part is at the last 25% of the vid.)
http://www.youtube.com/watch?v=28EFHmQedPo&NR=1&feature=fvwp