I use RMGI tapes and ATR tapes. I have a machine which can bias ATR at home, my Otari works well with it. For new tape, RMGI LPR-35 is all your Pioneer really needs. It's well slit, good consistent quality, and has output and headroom to spare. Maxell UD and XL1 are superb here and Scotch 177 and 206 and 207 are also superb choices. Scotch Highlander was my favorite cheap tape. On Pre-Recorded tapes, I like Magtec, late Ampex tapes, Pre-1965 Capitol, Decca tapes, Pre 1970 Columbia tapes and the old Bel Canto duplications and older RCA and Mercury tapes. I like master tape dubs and often have access to safety tape dubs.