Quick Saturday project. Being a large guy, the MPX just doesn't feel comfortable with its stock all the way out for me. It's far too short. I found that there is one company put there that offers longer rods, but their price and options were not what I wanted. I ended up going with 4.5" longer. 3.5" would have worked for me, but didnt know until I got it all together. I also added slots at every 1" vs the 2" that comes standard for more length options. Overall it added 5.5oz to the rifle. I could shave that down a bit more but didn't feel it was overly necessary.