It is an impossible situation to "feel good" about either way. I like the old adage of a bad decision made well is better than making a good decision too late. Which more or less boils down to the same sage advice from Mossdog.
If you want to feel better about your decision. It could be argued that the prospective tenants did not help themselves by leaving their previous place messy (assuming that the agent is being truthful). Whenever I have rented I have always made sure to leave the place as I would like to find it if it were mine when moving out.