Bathrooms generally are unpleasant,smelly places that regardless of what type they are,male,female,whatever,co-gender,are going to be smelly,people are going to go in,get to a stall whether it be toilet or urinal,do their business,hold their nose,avoid others,and leave. In general, I would say Transgender pose no threat since they are there for the same reason as everyone else, use it,hold your nose,and leave! It is funny, of the people that are so concerned about transgender in the bathroom,ever stop to think how many non transgender gay are there? some of them,aggressive to the max about their sexuality,but most just minding their own business.