When I sold the TST systems while full time traveling & weighing RV's I let folks know the cost of the repeater was low in comparison to the system price and for them to try the system without the repeater. If anything showed amiss, and after trouble shooting the valve cores to make sure they were making good contact with the sender unit, then a repeater was needed. With the amount of interference generated by all the electronics now in many of the trucks, the length of distance from the sender to the receiver and the quality of components used in manufacture of these RV's, a repeater solved many of the issues. Not all rigs required them and I only sold them when they were needed. I was amazed on how much distance the repeater added to the signal strength. I also liked the fact that the people at TST were so eager to help get any issue resolved. I called at times when I was sure to be leaving a message for a return call only to have someone actually pick up the phone and help me. I will always have a TST system on my rigs as they do work and work well.