All the pieces drop. I have collected all 4 sets.
So dont worry just cross your fingers.
Not to bust your bubble... I cant seem to figure it out the intended purpose of these sets. If they let you gain mana when you get hit, the chance of it happening is low even with full set and full burst level.
I have a human with 23k fame and karma wear the good human set, and I was unable to get the suit to work from being hit my monsters.
Then I tried 20+k good gargoyle set and same result.
Then I put on cloak of corruption and let myself drop to -5 level karma and used the evil human set... nothing...
Then I didnt bother testing the evil gargoyle set.
I guess I would like some spoilers or findings from other players.
Here's some of my findings.
Here each piece of the set equipped gives you Frenquency 1, when you have 5 piece of the set on it gives you frenquency 5, however when you put on full sets (6 pieces) your frenquency stay at 5.
The Karma Bonus: Burst level is your level of karma..
For karma 1-2000 Burst level =1, 2001-4000 burst level is 2 and so on and caps at 5.