Does anybody remember the pistol from Jet Force Gemini? It had decent ammo, which was limited, but if you ran out, the gun could still fire. The unlimited type of ammo was just really weak. Also, though you didn't classically reload the pistol, it could only fire around seven rounds rapidly before you had to let it recover (sort of similar to spurring Epona in LoZ: Ocarina of Time). This game mechanic meant you never would be totally out of ammo but mismanaging the decent pistol ammo could still make things harder for you.
Now that I got that out, I'd say my preference depends on the game mechanics. And, bottomless clip should not be allowed against other human players unless everyone has ridiculous levels of health or the bullets just don't hurt that much.