The video i put is from Left 4 Dead TV Spot #2 and i use some good sound for that!
also i have edit the video/song to fit perfect =)
i hope you like it, the song is ramallah - days of revenge from punisher war zone ost.
Backup the main files in case you dont like it
just place that folder into Steam\steamapps\common replace the files
whoala!

www.left4dead411.com
www.l4dmods.com