Flynn has a total of 17 TDs and 11 interceptions in his career.
By way of comparison, his competition for the backup job have the following:
Grossman: 56/60
Thigpen: 21/18
Ryan Fitzpatrick is 123/101, and Geno Smith is 25/34.
Fitzpatrick / Flynn or Thigpen / Petty is clearly the right roster for the season. Thigpen is a better rusher than any of the others, including Smith (8 fumbles in 2 years), but frankly I'd rather leave any of these QBs in the pocket as much as possible.