Bought it, played through to the end, it was 100% worth it! And sprites look great (except for goblins, i can't look at 'em).
Wiped my save and tried no-reflex run (literally only upgrading stats via shop or relics, trying to see how far i can get without LV training). And it seems vitality is kinda bugged there? Mo Oni is at 120 VIT and it seems that hit points never increased (38 damage reduces the health bar nearly entirely, and >60 dmg hits are insta-kills).
Kind of a shame, because i hoped for at least a tiny bit of replayability there with self-imposed challenges :(
Edit: Ah, at least there's a workaround. Equipping and unequipping DEX shift charm updates max hp.