For all of my revolvers that need moon clips, I use Ranch Products brand for my general practice and maybe the first loading while at the starting position in a match. Ranch Products moon clips accept a wide variety of different manufacture brands.
When we buy once fired brass, my wife sorts the Federal and Blazer together and then sorts the Winchester together. The rest gets fired in her DW Pointman 9.
For the 929,
The Winchester gets loaded in TK Custom standard .035" blue moon clips.
The Federal and Blazer gets loaded in TK Custom .040" stanless moon clips.
The 9mm reloaded ammo easily snaps into the Ranch Products moon clips.
The 9mm reloaded ammo gets pressed into the TK Custom moon clips by a needle nose pliers. I have 2 different moon clip reloading tools, but prefer doing it with a pair of needle nose pliers.
Not all cases of the same manufacture snap into the tighter TK Custom moon clip and rotate freely. I separate those live rounds and put them in a Ranch Product moon clip where it will have more play in it.
So, if I only had Ranch Products moon clips, I would try to only use Winchester brass. The Federal and Blazer brass would be looser in the Ranch Product moon clip.
No doubt for people just going to the range shooting and plinking for fun, other brass manufactures are fine, but in the action sports world where reloading is on the clock, some cases due to their "larger" dimensions don't leave the cylinder freely. A fired moon clip that struggles to leave the cylinder under the clock eats time and distracts the competitor.
That's why Federal, Blazer and Winchester are popular for 929's in action sports. Your 986 should follow closely to the 929.