We did one on March 2, 2017. Total cost for our family of 4 was just over $500 after tax. I speak for the rest of my family when I say it was the greatest 3 hours we have ever spent at Disney. The night we went, the park closed at 9 pm, so the AH were from 9 until Midnight. However, we went into the park at 7ish, so we got a couple of extra hours and were able to watch Wishes.
There were several reasons it was worth it to me.
1) We did walk on almost every single ride that was open. I think the first time we rode Space Mountain, we had to wait for one or two groups, other than that....zero wait time. I can't remember how many different rides we rode and how many times we rode each, but it was a lot for 3 hours.
2) Photo Opportunities. Our favorite pictures from our trip were from this night. Empty Main Street, pictures in front of the Castle with just our family, etc.
3) I remember being in front of TPOC and looking both ways and not seeing a single person. I made a comment to my family and the CM out front looked at us and said "Pretty coo, huh?" Yes, yes it was. Just a different feel and ambiance in the park that night that is really hard to explain, but it was flippin' awesome! We were the only riders in our boat on Pirates and the boats in front of us and behind us were all empty. It's the closest I'll ever come to having the park to myself.
Would do it again in a heartbeat.