Thought this might be a good comparison question to ask!
Mine get 5-6 hours of direct sun.
I have good soil and treat mine to bulb tone and azomite, so other than crazy weather (like this quarantine year!), the other major deal seems to be sunlight. My peonies are healthy and strong, but don't double/triple in size in a 2-3 year timeframe like some others have mentioned.
