I watched a video yesturday (can't remember the name of the guy sorry!) but he was at nex with these darts and he got torva plate.. now your probably thinking ok thats normal, but as has been discussed, and he talked about it in the video and zooms in on someone else, is at EXACTLY the same time he threw his dart someone else threw theirs and it even came up as a damage splat from someone else and NOT the guy making the video yet the guy making the video got the loot, something like that where the damage splat is yours and someone else gets the loot i can see people calling a bug.
I personally don't like these insta kill darts.. COME ON JAGEX SERIOUSLY!
EDIT:Had a quick look through my youtube history
http://www.youtube.com/watch?v=_206izGewJ8