What mods have you done to your XD and/or XDM pistols? I've installed a solid stainless steel guide rod, aluminum striker indicator guide, and a PRP trigger kit. I haven't notice much of a difference from the guide rod, other than weight. But I do have a Streamlight hanging off the front of the pistol which adds a bunch of front weight. The PRP trigger kit though has been awesome! It's a huge improvement over the stock trigger.