I came across some interesting AFP info at timawa.net In need of a compact boarding weapon (and/or a PDW for land armor crews), AND apparently put off by the high cost/time delays in buying H&K MP5's, or even the local Floro 9mm Subguns, the Philippine Navy (PN) and Philippine Marine Corps (PMC) have turned to refurbishing and upgrading some mothballed M3 and M3A1 .45 ACP SMG's. A version equipped with sound suppresor passed tests with flying colors last May (2004) at Fort Boni. Naval Station: These suppressor-equipped versions are for the Marines' Special Operations Platoon. The subsonic rounds make the suppression worth it for SOps. The 350-450 rpm ROF allows quick trigger fingers to let off single shots from this ostensibly full-auto only firearm, and increases controllability. Supposedly, the cost of reconditioning, upgrading and reissuing around 40 of these old warhorses is still less than the procurement cost of a single H&K UMP (a modern .45 ACP subgun). Lacking cash or support from the powers that be, the men and women of the Navy and the Marines get my heartfelt salute. The full article is here, citing info graciously provided by MBLT6/N11, Philippine Navy (Marines).