I don't know if data exists that says Primary or UPT does a better job of producing pilots... I seriously doubt that good data is available because the programs are so different and because the needs are so different for each service.
Post #327

Up until 1995 E-6 guys went through VT-31. Once the Navy switched from the C-130 to the E-6 they assumed the AF would make a better teacher with the reasoning that the AF flies heavies and teaches the type of flying E-6s do all the time. It made since at the time. Now that those first T-1 guys are COs/XOs, the T-44C has Proline 21 avionics (glass) and with the testimony of the civilian RAG IPs who have seen both advanced training products, E-6 guys are back at VT-31. I read the point paper that started the whole switch back. Bottom line summary...AF made very capable instrument pilots...USN made pilots that were much closer to being a heavy AC (PIC). Other main points were basic airwork during asymmetric situations and overall HW/SA during various situations including emergencies/system degradations.
I did not post this to restart the AF bashing but merely to point out why E-6 guys are back in USN advanced training.