Should I start Kolb vs Tennessee or Favre vs Green Bay?

Favre has not been playing well this season, however, he has played great against the packers beating them twice last year (over 500 yards and 7 TDs in those two games). Kolb is playing a titans D that has allowed 300+ yards 3 times this season (486 vs dallas, 386 vs giants, and 341 vs denver) however, the titans have a good p rush that has 24 sacks after just 6 games this season. I can't decide which one is the better choice.