I shot and developed Ansco later GAF slide film, did not much care for GAF 500, but GAF 100 and 200 could be quite nice. If you look at old Nat Geo editions you will find the pictures labeled with the film used, most often ANSCO. Most of my GAF slides have faded, all of my E4, E6, and Kodachrome are in good shape. GAF film was sold rebranded at many department and discount stores, KMart, FEDCO, and I think maybe Wards. I bought my GAF at KMART which later changed to 3M, don't recall if the change came before or after GAF left the market. Most of GAF black and white products were also very good. While in college in the 60s our darkroom instructor hated Kodak, the Great Yellow Father from Rochester New York, so we used a lot of ANSCO/GAF products.