On the topic of 24/7 turnout. My mare HATES living outside. She lives outside all summer but the second a storm comes rolling in she is tearing the gate down to get inside. In the winter she is inside all night. Goes out at 8am and comes in around 5. She will refuse to go outside if its too cold or snowing. Just the way she is. She is just a princess that way lol.
24/7 turn out doesn't work for all horses. However I would leave him outside in the summer if you can. Nasty Brat has her kool coat summer sheet and stays cool as a cucumber under it when its hot as heck and is happy as can be.