If you call it in a function c thisthat is bound to the input (otherwise you need to replace thisit with what captures the input), something like
$(this).parent().prev().children('span.street_address_display')
should take you to the span. In terms of efficiency, I would say that the biggest place you notice will be different from IE, or places that cannot be captured by a tag or class.
, , .parent(), , td, td, td, span street_address_display. , , . , .