I tried the FLGR KIT with the 18lb spring in my 1911a1 norinco build. I fitted a new military surplus USGI barrel and a national match barrel bushing. I did all the work fitting myself. I notice the FLGR speeds up the cycle timing buy cutting down on the over travel. The added weight up front keeps the recoil under two inches. She shoots cloverleafs and clusters at 25 yards no matter who shoots it.
Plus the speed in which it cycles she's a low budget race gun. I'm using Russian wolf 45acp ball ammo with this kind of accuracy. I haven't tried my 200gr swc target loads yet.
I noticed a problem on every 1911 I look at(used) the front rails show more wear over the rear rails. When I first tried the 18lb recoil spring without the FLGR I could hear the recoil spring binding as it coils as I pulled back the slide. I believe this added horizontal force is wearing the front rails more. On my new 1911's I installed the FLGR /18lb spring. One has over 500rds through it now with no front frame rail wear yet. All my 1911's have the FLGR installed in them now. Plus everything is lubed with moly.
I never had a reliability problem.
I haven't had time to experiment with the 16.5, 17, 17.5, 18 recoil springs standard and variable wound coils.
The improvement I'm seeing and witnessing in my norinco 1911 I have to say I'm impressed and 1911's rock. I would carry my 1911 anywhere with no fear of ever having any problems.
I also polish every feed ramp on all my new 1911's too.
Do not remove your FLGR, lube it and the recoil spring with moly and the frame rails.