reason for question (don't read if you don't have time to spare):
so I'm puppet master, my team has fed a riki to 19-4 or something stupid and I'm the only one doing decently (even though not that great) I farm alchemist bones, steam boots (str), buriza, 1 exile tall and I eventually get up to 3.8k, now I was on vent with some of the people that were doing terribly (who wanted to concede, I didn't want to though 'cause I hate doing so) and I was like; alright i'll get a divine rapier, if I die and drop it then I'll concede.
So I got it, was pulling off 1.1k and 2.2k (both procs) crits which was pretty insane..but eventually after like 3 kills and me running around as safe as possible I kill the fed riki (in 1 hit to my puppet) and he had the token of life and then basically I died rooftrellen picked it up, of all people.
so basically I was thinking, the Assault Cuirass and Divine Rapier are of similar prices, which one (as puppet master) would have given the greatest increase in DPS (taking into account my original items:
alchemist bones, steam boots (str), buriza, 1 exile tall) and does the puppet get -armour reduction?
as an afterthought I'm pretty sure an assault cuirass would be better as more hits = more chances to proc double crit.. but they would be a bit more than half as weak.
Assuming you're not worried about dropping it, Doombringer would more than double your DPS, Demonic Breastplate would only increase your DPS by a third, give or take a little. The only character where I would get Breastplate over Doombringer (again, assuming I'm not worried about dropping it) would be Pebbles due to his terrible attack speed/armor and probably the worst agi in the game.
The higher 4x crit argument is valid, but again Breastplate would increase this chance by 1/3 while Doombringer is basically guaranteeing a 2x crit every time with a slightly smaller chance for an 8x crit.