No idea. It is enough for ESV that it a) gets relayed to mi…

No idea. It is enough for ESV that it a) gets relayed to miners b) will get mined and not sit in CPFP purgatory. And as 250 < 500, the a) is almost guaranteed. And b) happens in next block ATM. If mining is inevitable, 0-conf is fine IMO. -- rt12