Most of the grips need a bit of "grinding" to fit on the smith and wesson and LMT lowers from my experience. Just take a little rubber off on the inside. Do it in small increments as it needs to be snug. You can usually set it in the sun for an hour or so or put it on some aluminum foil in the oven on low temp and heat it up a little and it will become soft enough to slide on. Take a dremel and a sand paper roll and make sure the area where your trigger finger and middle finger hit the grip is smooth. It makes transitioning from engaging to "off trigger" mag changes easier and smoother. Those scrape tools are nice, overprices but nice. I cant tell from the pic if the rail cover has a lock on each end or just one. If its on each end just cut it in half. If not I think I have some extra ones laying around somewhere. I prefer the slimmer daniel defense rail covers to the plastic ones because when your doing any kind of shooting/training in the rain the weapon becomes slick real fast. Plus the plastic gets super hot in Iraqistan!
Shooting with the foregrip close opposed to far is really mission dependant from my experience. When I am in a MOUT environment I tend to keep the grip a little closer. If I am in an urban environment or am shooting from a rest I push it out a bit. Alot of people get to focused on how fast they can complete a mag change drill. Keeping the weapon at the ready, controlled, and on target is way more important than having a 1 second mag change. Also some food for thought is mag change drills from random positions. I can promise you that I can perform a mag change drill from a knee better than laying on the ground. Alot of people buy the double mag clips. The little plastic doo dads that hold two mags together to help with changes. The problem most people run into under stress is finding a place to put the double mags during a change drill/scenario. Alot of what I am saying is easier to train that type. I The best way to practice smooth transitions is with what we call a dimewasher drill. We use these to help with trigger squeeze and sight picture. To practice the smoothest of weapon steadyness (like that makes sense) take a bore sight rod or weapons cleaning rod and either put some tape or cloth and wedge it into the bore to where its snug. Then to practice trigger squeeze get in a good prone position and lay a dime on the end of the rod. Practice squeezing the trigger without the dime falling off. Its harder to do than you think. For mag change drills we would use larger washers and other various items. Its also a good way to practice moving while engaging a target.
Anywho.. I am tired and need some sleep!