I tend use the splinter using TRF over TCR for temperature control. Just feel it's a better method if your mod offers it.
Basically the mods isn't reading the temperature but the resistance change to the heater wire as wattage is applied and the wire heats up.
Lets say that your using 316L SS for heater coil. TCR you using a line to decided how the it's reading these change's based on just one value. With TRF using a curve that takes muti resistance changes and values into account. See example below. First row of numbers is temperature second is the expected resistance change.
Problem is theres no real standard even within the same material one company 316 SS might read different than another company 316 ss depending on material quality. Add things like mica and mesh heater really finding the proper resistance values to enter becomes more of a pain.
TRF file
Temperature (degF),Electrical Resistivity
-58,0.923064
68,1
212,1.15
302,1.2
392,1.24
482,1.28
572,1.312
800,1.398
TCR
392, 124