I can't find complete box scores for the following SR games vs Utah: McMahon 1981, Nielsen 1976 & Sheide 1974. So I'm not going to count those games in the following stats - which is too bad, considering BYU won all three games by an average score of 46-20 and had 10 TD passes in those three games.
At any rate, here are what the following SR QBs have done vs Utah (listed by PER):
2009 Max Hall: 87.05 PER, 12 of 32 for 134 yards, 2 TDs, 0 INTs, 37.5%, 11 rush for 19 yds 0 TDs. BYU won 26-23.
1999 Kevin Feterik: 93.38 PER, 22 of 52 for 309 yards, 2 TDs, 3 INTs, 42.3%, 15 rush for -12 yards 0 TDs, BYU Lost 17-20.
1996 Steve Sarkisian: 107.33 PER, 7 of 12 for 70 yards, 0 TD, 0 INT 58.3%, 8 rush for 19 yards 0 TD. BYU won 37-17.
2001 Brandon Doman: 114.95 PER, 21 of 42 for 270 yards, 2 TDs 1 INT, 50%, 14 rush for 2 yards 0 TDs, BYU won 24-21.
1985 Robbie Bosco: 125.63 PER, 22 of 37 for 276 yards, 1 TD, 1 INT, 59.5%, (no rushing stats found). BYU won 38-28.
1979 Marc Wilson: 150.58 PER, 23 of 37 for 374 yards, 1 TD, 1 INT, 62.2%, 5 rush for -17 yards 0 TD. BYU won 27-0.
2006 John Beck: 169.07 PER, 38 of 43 for 375 yards, 4 TDs, 0 INT, 65.1%, 5 rush for 2 yards 0 TD. BYU won 33-31.
1991 Ty Detmer: 214.66 PER, 18 of 29 for 378 yards, 5 TDs, 2 INTs, 62.1%, 3 rush for -6 yards 0 TD. BYU won 48-17.
1983 Steve Young: 257.25 PER, 22 of 25 for 268 yards, 6 TDs, 0 INTs, 88.0%, 5 rush for -6 yards 0 TD. BYU won 55-7.
So since 1979 (not counting 1981) BYU is 9-1 with a SR QB vs Utah. The average stats are: 142.08 PER, 19 of 34 for 273 yards, 3 TDs, 1 INT, 56.6%.