General

keep %buff.

buff duration. helps with the OOPArts and your other buffs. Keeps you from having to use emergency supply so often.

all thief class require buff duration since the buffs only last like 2 mins

You look like a cute doll I would keep on my shelf ;3
And I'd keep 50% buff cos chances of +1 attack speed are so low

buff duration ind33d

Keep buff duration.

Keep the Buff duration hands down.

i say keep for sure. 50% buff duration helps alot with OOParts

I would stick with it tbh. Mine's just a measily unique 15% drop rate..
Unless there's absolutely nothing else needed to make your character "better" - this isn't even definitively better. It's down to preference for IA