I think Peppers is going to be regretting it a lot sooner than later. I honestly don't see any team giving him a contract equal to what the Panthers were offering much less more. And for that matter, teams are not going to be willing to give up that much for him.
Peppers isn't as good as most Panther fans think he is. And the reason being is somewhat a mystery. He has all the talent in the world but it just doesn't show on the field. If the stat line didn't read 14.5 sacks this season I would have guessed he had 4 to 5 just from his play. He isn't a game changer.
Peppers had his oppurtunity to shine, multiple times over the last two seasons. But at the end of the day he didn't. Don't blame that on the team or scheme or the players around him. Blame it on Peppers.