We bought a house that was vacant for more than a year. It had some evidence of a roof rat problem. We had a few weeks after we closed until we moved in, so we started pest control immediately. T2 caught or trapped all of the rats within a month or so. We kept T3 for monthly service and haven't seen any signs of rats since.
We also use them for regular spraying for bugs. It's pretty affordable - especially in an open desert setting.