If they put in an attachment system, It would probably work best as basic, maybe extensive if they knew how to pull it off. Personally, I'd like to see attachments alter things like reload speed (extended mag vs. taped mags) and weapon switch speed and run speed (scope vs. iron sights.) I haven't played MoH so I wouldn't know what that kind of gun customization would be like, but I'm assuming It's similar to what I mentioned.