I am putting a Wilson Combat 1 piece FLGR into a custom I am building for 2 reasons:
1. It looks cool in my opinion
2. I like the idea of a little extra weight in the front
Everything I have read suggests that there is not a large difference between a FLGR and a standard setup as far as reliability is concerned. Both work. I think the FLGR gets a bonus point for possibly limiting the chance of spring binding.
I plan to use a bushing wrench with this pistol, so I do not mind having a sharp spring cup edge. I doubt I will ever be caught in a situation where I must fix a recoil spring problem during a gunfight, but if I were, then that is where the extra weight from a FLGR would come in handy as I would likely be using my pistol as a bludgeoning device at that point.