those games got single player though and if you split the dustbowl maps up the games could end in 2 minutes. I really wish for another set of textures too, there's only so much good looking stuff you can make with all the desert stuff.
BF2 and Enemy Territory don't have singleplayer (well, they do, but it's complete and utter shit and basically just to figure out the maps a little and practice aiming). I don't know about Frontlines, but yeah, CoD4 does have a very good singleplayer (even if you can finish it in like 7-8 hours your first time through no problem.)
AND AND AND regarding Dustbowl.. DB1 is the ONLY one of the DBs I see ending in 4-5 minutes on a regular basis. Nearly every game I played in DB2 goes on for 10+, and DB3 is usually goes the entire time limit or very close to it (it's a bitch to cap!) It's generally no better or worse than my games of BF2, which last about the same amount of time. (Although maybe you don't play public servers much vesper since I only see you on when we do Sunday Sunday Sunday ehhhh vesper????)