In L4D2 - Dead Center - THe Streets, You cannot destroy the truck by the Save4Less, even with an upgraded M79
The L4D-L4D2 Assault Rifle is modled after a M16A2, but acts liek a M16A3. In real life, the M16A2 cannot handle fully automatic fire.
To make up for the censoring in L4D2, the developers added Counter Strike weapons.
The L4D2 Guitar looks to be based off of a Ibanez GAX-70. Also, Ellis will sometimes refer to the guitar as an "Ax," referencing to how many rock guitarists refer to their instruments as axes. One more thing, Guitars only spawn in Dark Carnival and the Parish campains.