If I ever sign up for Instagram, I will follow.
I figured in January I probably wouldn't need the Express Pass at all. I'm there for 2ish days (Tuesday and Wednesday - plan is to leave WDW first thing Tuesday morning, stay overnight Tuesday night, and fly home late Wednesday), so even if I wait in line, I should be able to get all the Harry Potter stuff done and hopefully hit up a few other things too.
I went to Universal for one day in late April 2017 after the Dark Side races that year. I got all of Potter done and went on Forbidden Journey 3 or 4 times even though it was closed until about 12:00pm that day.
I also recommend the Universal Orlando official app. Because Forbidden Journey was down, the app allowed me to set up a notification for what it opened.
In my one day I was able to do everything I really wanted to over both parks although I opted to skip a few things I've seen at Universal Hollywood in favor of more time in Wizarding World since that was the entire reason for my visit and passed on the nighttime spectacular altogether because I was tired (2 days removed from the half marathon). I ate at the Three Broomsticks and The Leaky Cauldron. Plus I bought lots of various Wizarding World sweets and of course had some Butterbeer (frozen variety as it was a hot day).
However, I would advise getting experiencing Escape From Gringott's done to your heart's content before buying the wand if you buy one. Small lockers and very long wand boxes might not mix.
I'm trying to decide if I want to get the wand or not. On the one hand, I'm a giant Potter Nerd and it feels like a must have, especially because I'll be able to spend as much time as I want exploring with it since I'll be solo. On the other hand ... I don't know if/when I'll be going back after this, so I don't know that it's worth it for two days. Adulting is the worst.
I had fun being chosen by a wand. My wand is Phoenix feather and it chose me because of Frank Costanza's legendary quote "I'm like a phoenix, rising out of Arizona." I used at the various spell casting places to my heart's content. I liked the ones in Diagon Alley a bit better than the ones in Hogsmeade.
All that said, I have not used it since that day as I don't go to Universal Hollywood that often. It is a lot of fun to do and if you're a huge Potter fan you might just enjoy it for the experience of it all. Just remember that if buy a replica wand belonging to a wizard seen in the stories, it doesn't do all the spells because "it belongs to another wizard."