Upgrade #3: E3D extruder.
Definitely one of the best upgrades of my K8200 printer is the E3D extruder with a 0,25 mm nozzle.
With the E3D heater cartridge the heating curve on my printer continuous fluctuated between +10° and -10° Celsius of the desired nozzle temperature and sometimes I got the famous brown out reset.
So I’m using back the original Velleman heater cartridge in the E3D hot end. Works perfect !