Depends on your style of play. If you are in a small building, you would be moving fast, and you will miss quite often. In that case, you need either a fast reload or a lot of bullets per clip. The good guns for close range, are the P90, it has 50 bullets per clip, or the PP-19, which has 65 bullets per clip. For mid range, the best guns are either AK-47, AK-74U, M416, and the G36E. If you want to kill people at long range, but don't want to buy the sniper rifle, then the best gun is the M416, because it has virtually no recoil, and the AUG-A1. That is also a good gun because it has average power, low recoil and good scope. But otherwise if you like a sniper rifle, then buy either the L9 if you want to kill a person from one shot, but if you buy that gun, you should be a good sniper, because you have one shot and then it reloads, and the person you shot at has a chance of running away. I prefer the Dragunov, because it has high power, same accuracy as the L9, and it shoots much faster, and has more bullets. As for the guns you listed, the M4A1, is not a good gun. It has average recoil, low power, it does not shoot fast, and it does not have good accuracy. The UZI, has very low power, shoots fast and has low recoil, but the problem with it is that the UZI shoots so fast, that you have to have good accuracy because the clip runs out fairly quickly. So basicly if you take an average, the best guns are either the M416, AK-74U, and the AK-47 due to its high power.