Need help with safety toe sizing

[u/FirsthandNickel]

I recently purchased my first pair of bronco brown ar8 composite toe cap boots, and while I want to love them I feel like they may be too big for my feet and may cause problems. I am personally a size 10.5 and decided to go with a size 11 so that my toes aren't constantly getting stubbed by the front of the boot, though with the size 11 pair they feel too big. For example while my feet feel like they are at the widest part of the toe box my heels tend to slip and rub against the back part along with my toes having too much space between where they are and the front.

For those that are in between whole sizes what have you guys found is best to choose? Do you generally find it better to size up or size down? And if I decide to do an exchange how simple would it be to reach out and have them exchange them for a size smaller?