Entertainment Promenade - Twin Suns bounty hunters drop Twi'lek Spinning Blades here in addition to the blades they drop on G0-T0's yacht

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[Snigaroo]

Seems like the two blade types are different as well. I think it was more likely that one sister was to drop one of the blades and the other would drop the second, not that the sisters would drop two of one type, then two of another.