We've had our Jungles since April last year. They were hatchlings born in DEC 2012 when we got them, and were right little chainsaws. Link is a little bigger than Caine now, and he's pretty laid back and doesn't really mind being handled. He will be a bit flighty when removed from his enclosure, especially if there are more than a few people around, but otherwise he comes good within minutes.
Caine was a demon when I first got him. In fact, Link was going to be my snake but we swapped because Caine was throwing himself against the tub trying to bite my sibling and her BF, they were a bit put off by that so I was more than fine with swapping. I was bitten by him like... 15 times in one handling session. Not to scare you away from Jungles, hatchling bites do not hurt, they might draw a bit of blood, but I would be more concerned about the snake breaking a tooth than my own hand bleeding.
Now though? Caine is the most laid back and carefree snake we have. I kept at it, handling him for minutes at a time per day-every couple of days depending if he was fed recently or not. He had it out for my thumbs, moving them would warrant a tag. He's still cautious of thumbs, but now he's been the only one that hasn't bitten me in a frame of several months. My sister's albino Darwin has bitten me more often than Caine has now that they are over the instinctual hatchling defensiveness.
What I'm saying is this, if you're interested in Jungles, they are not as bad as caresheets seem to claim. Maybe we just got lucky with our snakes being pretty chill, but I'm yet to see aggresive behaviour out of them. Defensive? Yes, especially when hatchlings. Aggressive however? No, not even at feeding time. Caine is the first snake (and currently only snake) I have and I wouldn't have had it any other way if I could turn back the clock and choose a different species. They are gorgeous snakes, the possibility of bad temperament didn't stop me from giving them a go. Well worth it in the end.