Are there some best practices regarding using strings and symbols?

For example I am processing XML and I might query it via xpath...

myDocument xPath: 'entity/@name',

or

myDocument xPath: #'entity/@name'

or

myDocument / 'entity' @ 'name'

or

myDocument / #entity @ #name.

So does it make sense to prefer one over the other here?

Any opinion/advice appreciated,

Peter