First off Buds came through and I had this before I had the gun and ordered this the day after the gun. I purchased this handguard for my MPX 4.5" barrel for a longer handgrip while using a suppressor. My Liberty Mystic X sticks out about 2" past this handguard (i wish there was an 11"). This product makes the gun feel lighter than the stock 4.5" handguard. Maybe it is balance..? or it is just a superior product. It is very light, strong, zero play after installation, and the coolest part is I can keep it in my pack to switch handguards on the fly. I ride a motorcycle 95% of the miles I put on and a jeep without a top the other 5%. A compact modular PCC setup can keep me shooting at any range, competition, or just over to a friends for fun. This is the perfect combination for your MPX and don't pass on this. Note that if i had the 8" unsuppressed I would still buy the 10" and get a longer muzzle device to clear the end of the handguard.