Its never worth it. Lol was end game content for when 5* was the highest * achievable. Its not to the point that wasting resources like revives on lol is such a waste. Just use the units and revive to get through story content instead.
With all the revamps to story content, does anyone think they'll eventually look at re-tuning LoL or Abyss? There doesn't seem to be much of a reason to do either (unless you're just really wanting a challenge for a lack of rewards and large use of units/resources).