Just went on this tour on Sunday. Here's a general overview:
Checked in at 11:30 and sat at a table to wait. I wanted to rest my legs. I ordered my lunch and was told we'd eat after. There turned out to be about 18 people on this tour, many of whom would ask questions and engage the guide, which was nice. The time between 11:30-12:00 is used to pass out audio devices, so I definitely recommend getting there early.
We had Michael as our guide, who was wonderful. We rode both Alice and the Railroad. Would have done Lincoln, but we got behind schedule due to audio issues and missing a train because of heavy ridership, and it's right before returning for lunch/apartment so we watched the pre-show and skipped it. It was about 2.5 hours walking, or I think that's what they were aiming for anyway. There was a 5-10 minute break where you could use the restroom or buy a snack.
I was part of the first group to go in the apartment. They do the separating for you. Two different guides showed us around, Craig and Amy I believe, while Michael took the rest for lunch. We spent maybe 30 minutes there? Hard to gauge since I wasn't looking at the clock. I was done with lunch around 3:45 or so, for what it's worth. All three guides, you could tell, really loved what they did and made the event so special.
They take a photo of you in the apartment and try to get the lamp in with you. I don't want to give too much information away, but there's a reason they pose you on a certain side of the room.
It was the perfect tour for me. All history and very little behind the scenes. I don't want to ruin the magic for myself.

You learn a lot of fun stories, some of which I knew. Some I didn't. A lot of imagineering information, which was cool. But nothing about the day-to-day. It's very much rooted in how the park came to be and evolved. And it definitely pays tribute to Walt. I teared up several times.
I'd definitely recommend for those who:
A) Love Walt; or B) Love history, especially of the parks
I would not recommend for those who:
A) Have children in tow; B) Are only there for the thrill rides; or C) Want a behind the scenes look
Even if you only have a limited amount of time, I found the 12pm tour time gave me plenty of time in the morning and the evening for doing other things. It was also during a busy day, so while following our guide through the crowds could be challenging, I didn't feel like I was missing out on precious park time.
Let me know if you have any specific questions. I'm happy to answer, so long as it doesn't involve ruining the tour for those who want to go in the future. The less you know, the better, in my opinion. Which is why no photos are allowed in the apartment except the one at the end.
Also, I believe the cost was around $110, but I can't be sure as I used a discount.