1. Scrap Metal
When I first saw this map, I thought the narrow passageways between the two building were a terrible idea, but there are plenty of passageways, even if they are all small. It's fast paced and you have to be constantly moving. There's nowhere to camp. It's beautiful.
2. Operation 925
Love the role destruction plays in this map, the office areas especially make duals interesting. Largest of the maps and the most interesting for gun master, thanks to the widely varying encounter distances.
3. Ziba Tower
Suffers from camping in all the rooms and the upper balcony, but is otherwise a solid map for CQD.
4. Donya Fortress
This doesn't feel like it was designed as a multiplayer map, but as an actual building not meant to be used in a game. I hate it.