We just got back. We started at the new one. Gringott's was amazing. Rode the Hogwart's express both ways more than once. No lines anywhere to be seen on the first day. Second day we went to Hogwarts. The place was packed. We went on a Wednesday and Thursday. Stayed on property and had the Express pass so we were okay with waiting in line for the Harry Potter stuff. Realistically though the line was never longer than 40 minutes for anything. The best part of the new Harry Potter is that you can ride the Hogwart's express back and forth. Both areas are small and compact. They can get very crowded even if there are not that many people there. We had breakfast at both the Leaky Cauldron and The Three Broomsticks. Exact same menu, nothing special but I did love the butter beer.
On another note, and not just the Harry Potter rides, if you are a person of any size other than small to medium please try the seats out front of all of the rides. I am a size 18/20 with most of it being in the bottom area. Yes---I am a fat bottomed girl. I fit comfortably in both Gringott's and the Forbidden Journey rides but could not get on either of the Dueling Dragons. It is better to try the seat before standing in line to find out you do not fit. There were several other rides that were just to tight for me. It was very disappointing. I fit in everything at Disney with room to spare.
Overall we had a blast. It was our first trip to Universal. They did a very good job with the Harry Potter end of things. It really is something to see. We spent way to much on stuff we didn't need but really could not resist. Weasly's joke shop is small and Honeyduke's is full of everything you could ever want to eat. Don't forget to head down Knockturn Alley.
