I found the MK parties to be significantly busier with real wait times. Yes there’s more rides but people gravitate to the same 4-5 of them. When you only have 3 hours but Mine Train and Space Mountain have 20-25 minute waits, that’s a big chunk of your evening.
By comparison, we did Everest three times as a walk on, Dinosaur twice without getting off, Na’vi twice without getting off and FOP twice. This was more worth the cost and felt much more “VIP.”
The big trick with the Studios and DAK events are to do the least popular attractions first, allowing the longest queues to clear out from day guests (Slinky and FOP) and the After Hours guests to do what they want. So, for example, start at Tower and Coaster, then head to Toy Story Land later in the evening.
My biggest gripe about these, besides the fact too many tickets are sold, it there should be a 30 minute window between when the park closes and the three hours starts. Clearing the queues from the day guests takes some time and it’s annoying to get in line at 10:01pm (or whenever it starts) and basically wait as long as a normal guest.