Who do you use in Call of Duty 4 Modern Warfare

Well, I personally tend to do best when I use the M4 Carbine. I also enjoy the AK47 and MP5 (silenced). All guns are good in their own respect, but some are better for others based on playstyle. Some people like large magazines so they don't need to reload, other's like burst/single shot weapons so they can fight at a longer range while maintaining accuracy. The guns I use depends entirely upon what challenges I need, game type I'm playing and map. Try out all the guns and see what works best for you.