I wasn't going to write a review as there seems to be blowback at times for not liking some people's favorite things, but my experience was very similar to
@mrmagoo22 's. First HHN. Went midweek with express with the wife. Neither of us were ever "scared". Probably less than 5 startles throughout. Very little unpredictability. You could pretty much figure out where the actors were coming from before you got to them. The best scares used misdirection or having identical dummies/actors in a room so you didn't know which was which. There just didn't seem to be enough of that. There was way too much "oh a hole in a wall, I bet theres someone about to jump out. Yup".
Unfortunately, the success of the event is also its weakness. There's just too many people. You are just constantly herded through the houses. You have to keep moving, and there's not time for the actors to really reset. Most of the time you've seen them jump out at a person 3-4 in front of you so you know where they are at. I'm sure the aftermath of covid and just the nature of things today limits what they can do. You know they can't touch you. They know they can't. That has to limit what kind of things they could throw at you and some chances for unpredictability. End effect, most houses you got to the end and was like "well that was disappointing". But as long as they get 10,000(or whatever it is) people to pay the upcharge for the event 5 nights a week for two months, there's no reason for them to change it. It's obviously a huge success.
In discussing it, we probably would have enjoyed it more with a group of friends that had a few easily scared people in the group. Our best house experience was probably Blumhouse because the guy in front of us about lost his mind any time someone jumped at him. We laughed all the way through that house. And because we were watching him, the actors were able to get us a couple times. Unfortunately, it was just us two, so not as easily scared the rest of the night.
All of that being said, we still had a good time. We had express the first night, and am glad we did. We wouldn't do it if we had to wait in those lines. We didn't do any houses the second night. The houses and actors were phenomenally themed. They are on another level on that front. Nightmare Fuel was a great show. We really enjoyed that. Overall ambiance was fun. Glad we went, but probably wouldn't make the trip for it again.