We home educated for a few years, it was a very positive experience for all of us.
Our daughter started at school in reception and we pulled her out in yr 1. Son never went.
As it turns out she chose to return to school last year, and went back in yr 4. Some started shortly after in yr 2.
Our son never had a negative experience at school but the natural course was to keep him out as his sister was at home anyway. It was the making of her, she gradually went from being too uncertain to come out from behind our legs at a party, to helping out at the local stables on her own 2 days a week, 9 till 4. She is self assured, resilient and calm. When she started school she would use all her emotional resilience just to get through the day away from us and she just melted down at home.
We would have kept them out and gone all the way through secondary had it been necessary. And who knows what the future may hold but for now, they're happy. The 6 yr old still finds being parted from me and his baby brother hard, but he is getting there.
Done well, and for the right reasons, HE is great. Personally I couldn't and wouldn't go down the 'unschooling' route, while I'm sure it works well for some, I fear it can also be done very badly.
Likewise when I hear people say that they are thinking of HE to avoid the stress of the school run etc that makes me twitch a little. Whatever our protestations about socialisation being an unnecessary myth, in my opinion kids need to be exposed to lots of different experiences to find their niche. So as home educators we were out and about every day, between groups, classes, trips etc. It was fairly pricey, and quite a juggle. One that we were happy to do, of course, but in my experience a lot of home educators like to say that you don't have to do XYZ, it doesn't cost much etc. Obviously that can be true, technically, but it would be naïve to pretend it is the norm.