i flew in S3s back in the days. late 90s early 2000s. They were an absolute blast. FSOs were meants to be a S3 transpant but it never worked out that way.
As to S3 fun factor, let me just say that after i moved to europe i would get up at 3am on sun-mon night to fly S3, go back to sleep and get up for work at 7am
Best sim experience ever.