Hello Sunchaser,
Using RT's will not function properly/at all..
First: The onboard BMS in a RT is not the same as in a XP. I doubt an RT can communicate with the master BMS.
Second:The XP's have a higher dischargerate then the RT's; XP 80A continue/ 120A peak. RT 30A continue/80A peak. in my opinion the XP's are nearly capable in doing their job: When accelerating the motor will pull over 200Amps from your batteries, when cruising you will need more than 80Amps, so the XP's are allready overstressed most of the time, using RT's will result in overheating the batteries and large voltagedrops.