Well from what we've seen from Gaiden adult Sasuke was more far more impressive than adult Naruto, Kyuubi and Naruto himself calling themselves rusty while Sasuke gains dimension jumping abilities and gets constantly wanked by Naruto and the kids. So it goes both ways really.
I would say on portrayal Sasuke was seen better.
Though in offense to Naruto, we didn't really see much from him either. We are forced to believe that Naruto has gotten extremely rusty where he was taken aback by a sword impaling him, where Kurama states that was nothing and his battle senses dwindled, but before this all happened Naruto had (in footspeed alone) grabbed Sarada and Chou Chou (who was about to be sliced by Shin) all before the attack ran its course.
And we are left with almost the same feeling with Gaiden Naruto ending the series by using the multi shadow clone jutsu and holding down the Shin's in base, and then finishing off the job with Kurama basically casting his "presence" on them all which could of ended this whole thing a long time ago.
Afterwards the movie tells us that Sasuke is on par with Naruto.
So we are supposed to believe, through this portrayal of Naruto, that THIS is the Sasuke that equals THIS Naruto? Or is it some future Naruto that actually trained and went back into fit shape? Either way you look at it the movie information is inconclusive to what is being portrayed.