We use the Pressure Pro system - covers both coach and toad tires and works great. The only problem we have had is that on very cold nights we sometimes get a low-pressure warning on the car tires. A 30+ degree temperature drop can make the air in the toad tires contract enough to reduce the pressure below the warning threshold. It only takes a couple pound drop on these low pressure tires (the warning comes at about 10% drop in pressure). I now set the toad tire pressure early on a chilly morning.