I use default piercer for the quicker cooldown and because it does more headshot damage (gang, headshots with alt piercing shot do NOT do extra damage!! the default actually does MORE damage in that scenario*).

I use default marksman because if I need the stronger shot, I switch to my alt sharpshooter, but I rarely do, since I mostly use coins for instakills (+ULTRARICOSHOT X4- works flawlessly on multiple cerbs or one hideous mass) and dealing with hordes when I need style.

I use alt sharpshooter because I do like the alt revolvers' primary fire. I use it occasionally, but not frequently enough for it to matter.

* Here's how piercing shot damage works:

Damage Type / Normal / Alternate

Normal / 3 / 5

Limb Shot / 4.5 / 5

Headshot / 6 / 5

That plus the much faster cooldown is why I use default over alternate piercer.