Caskets seem to depop rather quickly, which is irritating. I've been soloing DNC and doing Fields of Valor at the same time, so I'm in zones where I still get aggro, and mobs still take a fair amount of time to kill. If a casket drops while I have aggro/links on me, I have to kill the mob first and then get to the chest, and by the time I kill the mobs (EM to T usually) the chest is gone.

This has happened to me quite a few times, and it's starting to piss me off.
Maybe I should start bringing a PL/aggro bitch to take care of my aggro so I can open up chests.