I've not done mayhem-style events very many times but decided i'd give it a go to get the 1k bonus level. I figured it would take 5-6 hours based on damage levels and comments by others... After it took more than 10 hours to achieve that, blasting away with ep-53&O204 and reload buffs, i can say i've had enough of that BS. Went for entire hours with less than 15 points dropped.
So it's more of the same... waves of drops, etc.
My favorite is when i started repeatedly falling through the floor, and the mob i was killing did as well. It still managed to kill me, of course. I had to exit and reenter to fix it.
I was checking some time ago and IIRC it was around 1/12
Can't remember for level 50, but the last skill "adjustment" circa 2007 made 10k the new 8k for skill levels. If all other things were equal (they're not: SIB, buffs, etc), skilling to 8k in a skill now is the same effort as skilling to 10k in that level pre-2007 nerf. Those already at 10k in skills at that point basically had that skill doubled.
ETA: I was preoccupied shooting when i hit 1k points. Was the bonus awarded immediately or is that still coming?