Darius - Trinity Force vs The Black Cleaver?

The Black Cleaver (3100) +300 Health +50 Attack Damage +20% Cooldown Reduction

UNIQUE Passive: Dealing physical damage to an enemy champion Cleaves them, reducing their Armor by 5% for 6 seconds (stacks up to 6 times, up to 30%). UNIQUE Passive - Rage: Dealing physical damage grants 20 movement speed for 2 seconds. Assists on Cleaved enemy champions or kills on any unit grant 60 movement speed for 2 seconds instead. This Movement Speed is halved for ranged champions.

Trinity Force (3733) +250 Health +250 Mana +25 Attack Damage +40% Attack Speed +20% Cooldown Reduction +5% Movement Speed

UNIQUE Passive - Rage: Basic attacks grant 20 Movement Speed for 2 seconds. Kills grant 60 Movement Speed instead. This Movement Speed bonus is halved for ranged champions. UNIQUE Passive - Spellblade: After using an ability, the next basic attack deals bonus physical damage equal to 200% of base Attack Damage on hit (1.5 second cooldown).

Ok, now that the relevant item info has been presented, I'd like to say I feel like I've had much more success with Darius using Trinity Force than The Black Cleaver (among other unorthodox and possibly completely wrong setups like runes and masteries). Whether it's the ability to not be kited as hard with that extra 5% MS and Deadman's Plate, the ability to apply pressure in other lanes with Spellblade+[W] Crippling Strike, or the ability to unlock Noxian Might thanks to +40% attack speed+[W] Crippling Strike's auto reset, I find I'm loving the classic Trinity Force more than The "Recommended" Black Cleaver.

However, two things I'm not sure about: First, if The Black Cleaver's armor shred passive works with Hemorrhage DoT, that's a full 47.5% cumulative drop in armor against Darius's attacks with [E] Apprehend maxed out and no other armor penetration just for letting the stacks (which also benefit themselves if I'm not mistaken) tick on. Second, I'd like to note that the wording on UNIQUE Passive: Rage for The Black Cleaver specifies dealing physical damage and kills on any unit. This is important to note because Darius can still move during the startup for [Q] Decimate. So instead of stopping to AA a minion with Trinity Force, you start [Q] as you near a minion wave, hit one or maybe kill one, and not lose any momentum from Deadman's etc.

TL;DR: Which would you use and in what circumstances?