for dsm/xpenology esxi does support it and that why esxi might be your choice   dsm is kind of made for software raid and comfortably manage it, thats one of its strong sides (like Synology Hhybrid Raid - SHR) if you prefer the hp hardware way you can do it, esxi does support it (there are even hp custom images of esxi with all drivers included)   dependes on what you pefer and what brings better performance, you can have a 4 disk hardware raid and from that you have