Is there a difference between the PS4 and PS3 remasters?

As a longtime Kingdom Hearts fan, I bought the I.5 and II.5 Remix collections for PS3 the day they came out, despite owning all of the titles that these collections included. This was mostly to relive the series, but partially due to the fact that some titles had additional features that were either new or previously JP-only.

Today, the I.5 + II.5 Remix Collection was released for PS4. Is there any reason to buy this if I already have the I.5 and II.5 Remixes for the PS3? That is, are these strictly ports of the already-remastered PS3 versions or are there additional features of some sort that aren't included in the PS3 versions?

Solution 1:

There aren't any functional differences in the games in terms of content. You're paying for the same content, just on the same disc versus two different discs. However, Square Enix significantly decreased load times for all of the games in the collection. Further, they play at 60 frames per second.

Trophies from the PS3 version don't carry over to the PS4 version, so you'd have to re-obtain them all if that matters to you.