Coming at it from the other side, one of my dc went to a secondary school with an annual intake of 90 (three forms), and the head and deputy still didn't know most pupils' names. 
As others have said, as long as the school have got the structure right in terms of form groups, house groups, vertical tutoring, there's no reason why it can't be fine. If you go and look round you should get an idea of the quality of relationships between the staff and pupils - look for pupils chatting happily with staff, teachers addressing pupils by name, and basically everybody looking as if they want to be there and are happy. Look at the size of the individual tutor and teaching groups as well - although admissions are done in multiples of 30, there's no reason why a 180 pupil entry school can't have seven forms of 24 or 25 rather than 6 forms of 30.
My youngest dc is in a school with 180 intake, which I guess is average for a secondary, but twice as big as oldest child's secondary. All the deputy heads seem to know who she is, and I've been approached at school functions without my child being there and had a teacher say, "Oh, now let's see, youre x's mum, aren't you?"
Really, the overall size of the school doesn't tell you anything, it's all in the way it's organised and run.