I honestly prefer AKs but i would have to concur with an short m4. I they can accept all sorts of grips, lasers, scopes, flashlights, ect. (if it has rails). It's normally a faster reload as well since the mag smoothly drops out instead of you having to manually remove it... so you can grab the next mag while the 1st mag is still in the process of dropping out of the mag well (not that important but I'm just trying to sound professional) If you want something different than an AR-15, i would probably go with an short AK or G36c. :EDITED >Another gun I think you should look @ is an AUG or TAR-21. Short guns with long barrels are great for any situation. O:)