I can confirm that the pirhana can open with certain biners.
I use the shark (nut tool+knife) on trad rock climbs which has the same blade design. MOST of the biners that have a reduced cross section (DMM live wire, BD neutrino, camp nanowire) leave enough wiggle room for the blade to possibly come out.
No issue with fattie HMS's, don't recall if the "I-Beam" cross section provides enough bulk to avoid this.
just keep that in mind.