I have only good things to say. They come to my house to install, calibrate, and remove the device. If you have a problem and call them, they pick up the phone and resolve the issue.
I had gone on a trip without turning off the breathylzer and when I returned I had no battery.
(No battery because I did not know to turn the installer off). I had to have the car towed.
This was not the companies fault. But they went to the shop and paid the money for the new battery.
Use them. They are great.