In our campaign world most buffs have visual effects, that might be strange going to bed with a shield of faith lighting the room.
The opposing dispeller needs to be atleast 1 level higher then the person that cast the permanency. It's why I recast it every level. And I think even then it only suppresses it for a bit. Not sure about the suppressing part but sure about the atleast one level higher part.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.