Well i use the Brutalizer for Bosses, but TF is an amazing Trashtankweapon. In MH you can only hit 4 target with TC every 4 secs to get the 20%debuff up, but with TF it is no problem.
Very usefull, it is between some sheeps, u have 20% dmg reduction on meleedmging trash, while standing next to 3 sheeps and 1 sleep.
And every boss where u have a 2nd tanking roll, like add tanking etc and u cannot wear dps gear, u can use the TF to support your mt, maybe a resisted TC can be avoided by a lucky proc

Well other ways to use it:
-Procs on Supremus look great

-Shatposing
-and answering the question: "where does it drop", replied by: "MC", and another: "where?" , "Molton Core", /2 LFG Molton Core
Well i dont know if it is worth, cause i am one of the once, just doing mc 4 fun 3times and completing it in 3 weeks. But on the other hand, it is very easy to farm it, u just need 10 good friends