Rogue Assassin & Raider's Reward Box

[Dulcimerist]

My rogue assassin (TWF with daggers) is suddenly at level 24, and I see that she still has her Raider's Reward Box in her bank. Should I probably use that now and grab Agony? Her next two lives will be rogue, when she gets around to TR'ing.

At the moment she's still dual wielding Guardian of the Liturgy, and also has a red-slotted vorpal dagger of assassinate.

This is my first time in epics, so there's a lot of gear I'm not very familiar with. If I do grab Agony, is there another epic dagger that I might have fun with in the other hand?

[Sunnie]

I'm not going to recommend anything regarding how you use that box, but as far as daggers go...

The night revels are still way off, but the spectral dagger from there looks neat. Else maybe a thunderforged with Dragon's Edge for 35% fort bypass and an average of 69 bleeding damage on crit, take 1st degree burns at tier 1 and you inflict vulnerability as well.
Most of the other really good stuff I can think of is level 28 and up.