You're going to end up with shredded chicken either way (unless you want to keep your chicken whole), so the cut you use is totally up to you. Bone-in is generally tastier, but boneless tends to provide more meat. Either way, I must say, the Instant Pot always delivers tender juicy chicken. Boneless chicken breasts are generally my preference as they are meaty and I don't have to worry about the bones. If you do use bone-in, you'll want to cook them for 20 minutes just as you would frozen chicken. Keep an eye on the amount of liquid required. Bone-in vs boneless produces different amounts of liquid when cooking.