We must be mad giving a potentially dangerous muslim theocracy like Saudi Arabia such an advanced weapon system. It’s a well known fact that their society is hostile to the west and it’s values. If the monarchy ever fell or succumbed to internal pressure to adopt a more hostile position, we could be faced with having to fight an enemy that is better equipped than more recent ones who had to make do with clapped out Russian crap from the Soviet era....
The Suadis military purchases are strongly influenced by political considerations. They bought the Eurofighter to get European support.
As for them being used against the West, it is unlikely. Once the maintainers and techs leave, the systems will all be degraded, down or grounded within weeks.
The Saudis order operate the largest export fleet of F-15S strike aircraft(around 70 aircraft).