With OPs exact build, or with
Bladedancer (32) / Assassin (20) / Nightblade (14), it makes little difference for me over a three minute parse on the Boss Dummy.
It starts high around ~600 DPS but goes flat at 500-510 DPS. Final Blow specced is 536 Damage, vs 516 for Deadly Strike, not sure those 3 points in Sin to boost FB is worth it. Deadly Strike should be 520 with Fire and Death Attunement at 3 points.
With
Bladedancer (32) / Assassin (23) / Nightblade (11) should in theory be more optimized, as it lends 15% passive and 15% from rear attacks to Final Blow. FB is 528 damage vs 508 from Deadly Strike.
Again, the parse flatlines at 500-510 after 3 minutes.
This is with only 356 AP, 20.77% Crit, and 26.2/25.5 DPS weapons.
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