Hi George, members.
Dusting off the cobwebs I seem to recall the emitter resistors oppose hfe as emitter current increases due the higher volt drop taking place - this is their purpose and allow each parallel device to balance.
Given we are talking .6v turn on you can see that not much voltage is required to throttle back the transistor drive, so scale your emitter resistors accordingly e.g. if 10A flowing then only 0.06 ohm will give you 0.6v but still dissipate 6W of heat.
Also don't forget those transistors will be cooking too with Vce*Ice Watts each and are subject to thermal runaway if not controlled. Mosfets have a positive temperature coefficient and therefore don't runaway, instead shut down as they get hotter. I hope this helps.
Regards,
Bill
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