Putting together a new AR-10, considering Luth-AR MBA-1, Magpul UBR (with scabbed cheek riser), Magpul PRS3, or XLR Tactical or Extreme buttstocks. I have used all of these except for the XLR’s.

Taking a long shot here, has anyone used them? How is the weight balance? How solid is the cheek piece over the top for cheek weld? I assume the LOP and buttplate adjustments are rock solid - but can anyone confirm?

The PRS and UBR are pretty heavy among these I’m considering, where the XLR rather light. I can add some mass, maybe a quarter pound if needed, to the XLR. The front end will be a 24” barrel with a .936” gas block - very heavy barrel - with likely another pound of ARCA rail and blocks out front too - so a little extra “mass in the @ss” might not be a bad thing. I shoot free recoil, so my cheek weld isn’t hard pressure, but flex in the cheekpiece does cause me a split second of consideration on stages, so I do have to modify the Luth-AR to eliminate the little squish it has.

This isn’t meant to be some prepper battle rifle, nor a backcountry hunting rig. I know the XLR’s aren’t very common for AR shooters, and I know this is a long shot here, but I’m asking around.