Cool, I didn't know about the importance of the inductor DCR. I have been buying a Coilcraft 100uH with 220mOhms max DCR so I'm excited to make a possible optimization there. Mostly I've just upgraded the MOSFET and diode to more robust parts. My first iteration failed after not too much on-time, not sure which component blew. But it used more baseline rated components and a 220uH (330mOhms) inductor which may have been too hard on the circuit? I dunno.You need a decent inductor though, low DCR
How are you load testing, you just lower resistance to ground on the output of the converter until you see the converter output sag? Maybe I can do before/after test on that inductor.