Kind of a weird fact about H1 is that its 'work hardening,' and the act of grinding it increases the hardness.
So PE H1 has pretty mediocre edge retention, similar to Aus 8 / a bit better then 420HC (and subsequently sharpens very easily.) RC hardness is reportedly in the 56-57 zone.
But on the flipside, the act of grinding Serrations into the blade dramatically boosts the hardness - reportedly as high as RC 67. Spyderco has reported that SE H1 has the longest edge retention in CATRA testing of any of the blade steels they produce.