What 4redsyourdead said sums up the school very well, as do the previous posts. The ACS flying training part of the course is to a very high standard with very good first time pass records, hoping i can join the trend soon! The fact they also conduct the entire CPL on the arrow is a great bonus which is not often recognized, and the CPL cost is still very competitive with other schools using the archer or equivalent for those first 15 hours.
There is actually an even better value hour building agreement now between AST and ACS providing you sign up to complete the CPL with them. ACS dedicate a C152 to the AST students at £85-90 per hour wet with good availability which is hard to come by at any school.
The quality ACS flight training paired with the AST ATPL residential groudschool makes it a hard package to beat.