Fantastic idea to visit.
Also, once you have seen round and (hopefully) liked one or more of the schools that you have applied for, take your child round [I would suggest that as a first visit for most people, but given your concerns, I would suggest an 'adult only' version first for you].
The school DS went back into after a period of HE was the one where the Head put his hands down to my 6 year old and 4 year old and said 'Can I show you my school?' TO THEM, leaving me trailing in their wake. It is a large primary, but that initial impression of focusing absolutely on the child and doing things for them, not to impress the adult, was absolutely accurate.
Why don't I HE any more? Short answer is because the issue was not 'School' but 'A particular school', and a school move following a house move took away the problem - even for my deeply quirky, spiky ability profile, many ASD behaviours DS.
Longer answer related to a wish for him to access specialist teachers at secondary, as although I am very expert in some areas there are others where I did not want to deny him the experience of learning from someone with a much higher level of expertise than I can offer (and had I HEd DS through primary, the spikiness of his academic profile would have made him very difficult indeed to reintegrate into mainstream seconary - his primary head, when I deregistered him, opined that he was a child who was unlikely to be able to re-enter mainstream education.). Also, for a child who due to a level of ASD has to explicitly learn the social norms and appropriate social behaviours of e.g. conversation, working in a group, playing a game without strict 'rules', keeping him permanently away from an environment where all of those ARE appropriately modelled and taught every day [supplemented by daily work at home, of course] was only likely to intensify the difficulties.
DD, on the other hand, was born conventionally school-shaped - to have kept her away from her natural environment by HEing her would have been positively unkind!
For what it's worth, neither of my children noticed that Year 2 SATs happened (and they are observant children). DS did notice Year 6 SATs, but his school does minimal preparation (in the form of familiarisation with a couple of papers over the course of the year) and overall he seemed to see it just as a challenge along the lines of the weekly 'tiumes table challenge' rather than as any big event.