When they worked together till now. CM Punk was and is more over with the fans and critics.Cena has made the WWE more money than Punk ever did and ever will. The guy is a star and I'm not even a big fan of him.
Punk had hype but notice is still just the pipebomb promo. The guy got battered in 2 real fights so can't exactly be cutting promos saying he's going to kick people's arse. He will draw for a while but at 42 he won't have long left and will hopefully be in the putting over talent section... especially after criticising other older talent for not doing it.
What happened before they worked together is irrelevant when comparing them.