First of all, it's too expensive. I lucked out that my playthrough of kh3 ended in december, so I was able to snag this a few weeks later on sale, but I had it wishlisted for a few months before and it never dropped in price.
That being said, it was very fun to see what all your friends were doing while sora was doing the final fight. It was an epic fight too, and I thought it was done well.
The data fights are absolutely brutal, and are designed for all those people who dared to complain that kh3 was too easy. these are not easy.
Now for the cons, I'm pretty sure the voice actors for some of the main characters were different. Also, the mixing was wildly off for some of them. being too low, and not even sounding clean.
Also story wise, it does feel like a bit of rehash of the end of 3 until about halfway through.
It's a messy DLC, but there is still definitely something for everyone if you loved kh3.