I have read the same thing about arus! I own an adult female aru and she is as calm as the day is long! She just laid eggs on April 2nd and didnt even attempt to strike at me when I took her off the eggs which is VERY RARE! I have an adult male sorong and he is a doll baby as well!

A lot of it depends on the snake and if it has been handled since its youth. But in general arus and sorongs are both mild mannered during daylight hours! Almost all gtps are aggressive at night and your hand should never enter the cage once the lights are off or the first ten minutes they are on!