I don't regret it... but it's different.
I didn't leave DS long enough in mainstream ( he left in reception and went to an out of borough special needs school) to see how things panned out. However, DS had a very severe and complex speech and language needs and I knew the longer he stayed in mainstream he would find it extremely difficult to access the curriculum.
In his mainstream school, he was happy, a lot of the children from his class liked him, the parents were really nice. Socially he benefitted a lot from being at his mainstream school. Though, there was a time I had a meeting at the school and I saw DS in a corner playing with some toys whilst the rest of his classmates were working. I want my son to be included, not singled out. Also, as lovely as the staff were and his 1:1 were, they are not trained in teaching children who have SLCN and was sometimes at loss what to do with DS ( the school isn't good for children with SEN).
In DS SS, he is actually learning, his taking part in group activities, their therapy provision is excellent. It was the school ( and the therapist who works at the school who wanted to work on this) that got my son to say "Mum" for the first time and since then it's non stop. My son went from saying 5 words at 5 to 200 words and combining 2-3 words sentences at over 6 and a half, since joining the school. Whilst at his mainstream school, and I wish I didn't listen ! They told me not to work on DS reading skills ( till he gets enough language) and kept sending home reading books with no words in. Whereas as soon as DS started at his SS, they told me that I need to be working on his reading and gave me books, which were suitable for him at his current level and has words in !
To be honest, I think I was a bit selfish. I wanted DS to gain language so that his able to navigate the words, gain friendships to socialise. Having speech therapy once a term at his MS want going to cut it.
However, I very much miss the social aspect since leaving DS MS, I probably wouldn't of felt like this if he went to a SS in borough but as he goes to a school out of borough, it's very difficult to get to know the parents and set play dates as they live all over the county.
In hindsight, yes I made the best decision to put him into SS. Having worked at a MS, the MS curriculum is very fast paced from year 1. Yes the child will have their own individual curriculum but there isn't enough hours a day to do this as the child who has difficulties needs to work on his : speech and language targets, fine motor, DD spry breaks. I also visited 16 special schools so that I knew I made the right choice and only that school ( the 1) where my DS currently attends was the only one that I knew was right for him.