I m a big fan of madness and at lvl 39 my current build is: http://www.torhead.com/skill-calc#200ZZfMforbkrf.1 Crazy thing is i really love the healing droid. Do ok with Khem and Andronikus but with the droid leveling in pve is really easy going! I dont have downtimes anymore between the fights. Can only recommend that people give him a try.

I m a full Madness lvl 36 assassin and used mostly Khem till about lvl 30. Then i got more and more trouble as he falls too quick or at least gets too much damage in "normal" fights. I tried Andronikus now and then and with him its quite ok for my playstyle. But just as the same as with Ashara i have to regenerate after every fight (which i hate). Either me or the companion takes too much damage everytime. I now tried the healing droid and well... its amazing! He has only 3 items at his lvl and heals like crazy. I finish fights against golden enemies (+adds) with at least 80% health and have no downtime against normal mobs. I m quite curious how he heals with good equipment. I know i get a better healer later but if others too cant find the suited companion for their playstyle i can really recommend to give the droid a try.

Ive played full madness till lvl 30 and had zero problems. Was alot of fun! At 30 i noticed khem started to fall too quick and when playing with Andronikus its like him or me half health down after a fight. Whoever had the aggro. Then i tried full darkness build and well... it just isnt my playstyle. Hitting like 2,3 buttons and wearing down enemies is not the view i have from assassins. I never would say darkness is in any way weak, just wasnt the right thing for me (i m even sure i play darkness far from optimal) Switched back to madness, tried to play a bit better (i know i m not a good player^^), took a closer look at khems equipment (which i hadnt spent much thought before) and it works again for me. Madness is just much more fun for my playstyle. Just an info that madness can work as well while leveling. At least till the mid 30s as i m not higher.