Two identical 250 mOhm resistors in series with the MOSFET sources will help improve the current sharing between MOFET and prevent electroThermal instability that, in linear operated MOSFETs in parallel, could cause positive feedback and eventually MOSFET destruction. See for instance "MOSFETs Withstand Stress of Linear-Mode Operation" (powerelectronics.com/704PET23.pdf)
or "New 500V Linear MOSFETs for a 120 kW Active Load