Troubleshooting Smartrise is a horror when the problem is not your typical door lock or gate switch failure. Take a look at the prints, the information given is very vague. They give you point to point of the main circuits but nothing else. I agree when they run they run smooth and tuning them up is fairly easy but when problems arise they are not your easy to find like your typical MCE. All 3 SRU boards are interchangeable but you need to download the program into each board before use.