Has anyone had any experience with this hydraulic recoil buffer? Is it for real or a spendy gimmick? I have a 20" bbl varmint upper to hunt tiny sage rats, but recoil is still to hard and I lose the sight picture in all but the lowest zoom settings. Seeing the rat go up "in smoke" is 95% of the fun! How much will this AR recoil buffer help me maintain the sight picture?