just depends on the enemy players and or class, because some classes can solo lifes 1on1 while some others have problems doing so, it also depends on the player, i cant possibly understand how warriors can fear life offs when they have 3 high damage skills, lysis and first aid, or why mages insist on running away when they have enough damage to do so as well.
In theory no class should rly stand out vs multiple charas and kill but it does happen in some situations, like for example if im on my templar i can survive 2-3 sins at once, priests shouldnt have probs vs melee until they are reliefed and lifes should tank defenders/sins easily (just beware of darksword - painsharing)
www.ryl-calc.de.vu
you can calculate the character stats there