Are Holy Symbol mules still worth using, and can they go to the higher level places?

Since LHC and SH are party play areas, you should not be using buff mules that are too low-level to leech unless you have no choice..

Oh, I see. Regardless, I wouldn't mind having an HS symbol just for lower levels then, seeing the lower levels tend to be the worst in my opinion (as in having to fight for Haunted Mansion/Alien maps).