Inga.
Warslinger fungerar bara med den vanliga slingan.
Detta förtydligas i Vanliga frågor om Advanced Race Guide :
Halfling, Warslinger: What kind of slings does the this reload ability work with?
The warslinger ability says, "Halflings with this racial trait can reload a sling as a free action." It doesn't say "any type of sling" or "all slings," just "a sling." The ability only affects standard slings, not halfling sling staffs or any other kind of sling.
(betona min).