OP, it's a controversial subject. I think it depends a lot on how you are as a family, and what values you want for your children, how you want them to grow up.
I will say though, based on having been a day student at a boarding school and my own dad and grandmother being sent away to boarding school at respectively aged 11 and 7 (! this was in the late 1920'es though, so very different times) that sending them to board before 13 seems to early for the child's developmental stage, unless there are special circumstances like the parents being unfit to parent or being posted in dangerous locations etc. My grandmother suffered lifelong detachment from her parents and struggles to express love and form close relationships, and lo and behold send her own son away to boarding school at 11, which he hated. He missed home terribly, and I can tell it has impacted his emotional development negatively. He is very reserved and in some ways strict. He did, however, love boarding once he became a teenager, because of the freedom and opportunities to be independent and hang out with friends all the time. And that is the same I saw in the boarding school where I was a day student - that after around 14 - 15, it's a great option for many teenagers, provided that they are thriving in the school. Because the thing is that boarding school is fantastic if you're on top of the hierarchy and hell on earth if you're at the bottom. Because it's 24/7. So it can be a risky choice, so if you make it, be prepared to keep a close eye on how your children are getting on and be prepared to make changes if they're not thriving.
In terms of values I'd say boarding school is great for building friendships and if you want to/can afford a fancy one, building contacts and that much criticised old boys/girls network that will help you all your life. This is if that's what you want for your children. It can also be great in building independence and teach the values of the particular school.
Having your children at home with you gives you the option as a parent to influence them and keep looking after them, and for me personally, this is definitely the option I will choose. If my DD at some point herself expresses interest in going boarding once she's a teenager, for the experience, I'd be more than happy to accommodate her, but I would want to initiative to come from her.