A minimum of 15 wins in HD really isn't a fair comparison to 15 wins in RL with the disparity of games played.
If you twist the numbers the other way and ask for teams with 12 or more losses getting at large bids here are a few;
2010: 9) Louisville, 10) Georgia Tech, 10) Florida, 11) Minnesota
2009: 9) Tennessee, 10) Michigan, 10) Maryland, 12) Arizona, 13) Mississippi St
2008: 9) Oregon, 10) Arizona, 11) St. Joseph's 12) Villanova, 12) Kentucky
2007: 10) Texas Tech, 11) Stanford, 12) Arkansas
2006: 8) Arizona, 8) Kentucky, 10) Alabama
none lower than a 13 seed. More than half a 10 seed or better.