Our club have an old AMB RC2 decoder and we will send it to Mylaps to be upgraded to the new Mylaps RC4 decoder. We did notice on the New Mylaps transponder we are having issues with the transponder not getting picked up and sometimes it shows different transponder#... I called Mylaps today they basically told me that we have to upgrade the old AMBRC2 decoder to the newest Mylaps RC4 decoder for us to continue racing without conflicts reading the transponder. For $350 its not bad but with sofware they are developing the old PT will no longer work so everyone will be force to use the new Mylaps RC4 transponder talking about monopoly.... A lot of us still use the old AMBRC PT and all of the new guys have the newest Mylaps transponder so it will suck to all that have the old AMBRC PT....