Ok, I run as affliction/destro, and have some choices to go with. As far as trinkets go I have a DMC and I can either pair that with either reg heart or stump.

Obviously, the hit that I lose when using heart over stump needs to be made up in other aspects of my gear, resulting in a lose of haste.

us.battle.net/wow/en/character/stormreaver/eid%C3%BCs/advanced

Too give an idea about my stats with stump, I run with 17.00% hit and just over 2000 haste, int maybe a bit lower then that showed in the link but not much.

The way that heart works, I cannot use it at the start of the fight, until the stacks come up, but it also gives me the control for when to pop it.

Questions I have are
Is heart worth using with heroism?
Are the stat gains using stump for hit, worth using it over heart?
Any advice or tips on the two trinkets in boss fights and when it is best to utilize them(stacking with DMC, boss mechanics, pots, ect.) is appreciated.