Ti'tahk, the Steps of Time vs Runestaff of Nordrassil

[Twosteps]

Hey guys, has anyone been able to get a clear answer as to how good Ti'tahk is for warlocks? (specifically, I'm playing destro)

I just got it today and I'm not sure whether or not it's worth it for me to drop the Runestaff - I ran some tests on Simcraft and it shows Ti'tahk giving slightly lower DPS (36900 with Runestaff vs 36600 with Ti'tahk or so).

My current stats are 2700-ish haste, 16.03 mastery, 14.2% crit and 17.1% hit. To use Ti'Tahk, I have to reforge extensively, leaving me at about 2440 haste, 16.96% hit and 14.51 mastery. I'm guessing the loss of the DPS is due to the fact that I no longer have the haste threshold required for immolate's 4th tick during lust (2681), and a significant drop in mastery. My set of gear as it is right now doesn't allow me to reforge haste back up to 2681 with Ti'tahk equipped, is that a minor DPS thing or is it vital for destro? Simcraft also shows Ti'tahk at about a 20% uptime, but I just tested it for myself on dummies and it seems that the proc chance is REALLY low. :\

[Deleted]

Keep in mind it also buffs your raid members.