Yep, Infineon OptiMOS5 or Vishay SIRA20DP/SIRA60DP would be nice Mosfets in the SP70 or other Sofirn flashlights. OTOH, I doubt it's worth all the efforts for pushing a single XHP70.2 to its very limits. 8000lm equals to probably 20amps which is close to the absolute maximum for this emitter. Maybe Sofirn could try a linear driver with constant current regulation like Noctigon K9.3? It would be nice to have lets say 6-8A regulated which could maybe maintained indefinitely with such a big light, see Convoy L6 with the FX31 buckdriver for comparison.