I've noticed that some addresses in the continental USA get scores >90 when geocoded with ArcGIS Online while zoomed out on the map to the entire continental USA even though the same address gets a score <90 when geocoded with ArcGIS Server 10.3 and the most recent bundled StreetMap USA address locator.
6330 71 ST N, Pinellas Park, FL 33781
Address: 6330 71st St N, Pinellas Park, FL, 33781
ArcGIS Online Score: 100
405 CIRUS AV S, FL 33765
Address: 405 S Cirus Ave, Clearwater, FL, 33765
ArcGIS Online Score: 92.43