The new iPhone 7 and iPhone 7 Plus come with three storage options 32GB, 128GB and 256GB and you would expect all of the storage in Apple’s new iPhone to perform the same.
It would appear that Apple uses faster storage in the larger 128GB and 256GB models of the iPhone 7 and iPhone 7 Plus than they do in the 32GB model, have a look at the video below.
According to the video from Unbox Therapy the 32GB storage in the iPhone 7 is actually slower than the storage on the other models.
This can be seen when transferring the same video to both devices, it took 1 minute longer to transfer the file to the 32GB model.
Source Unbox Therapy, TNW