Israel Weapon Industries (IWI) recently posted a video of them running the current version of the UZI PRO through some mud torture testing. I recognize that any promotional video can be edited down to just the parts that make the gun look good, it is nonetheless interesting to see that the gun can run in these conditions.
For those that are not already familiar with the system, the UZI PRO is a 9mm SMG that fires from a closed bolt and weighs about five pounds. Due to its compact size, it can make for a good weapon for protection details.