While this was one of the most challenging things, I have done, Inca Trail Reservations made it clear and easy. Aside from a somewhat hasty orientation, everything was well planned, and since there were a lot of cities and modes of transportation, that made it so much easier for us.
In terms of trek itself, I was the slowest hiker in the group, and there were parts that were intense at such a high altitude. If you are a slow hiker, it helps to bring snacks, especially for the second day, as lunch is at the campsite and you will be hiking for a solid 8 hours. Our guide, Victor, was fantastic. He was super knowledgeable, he made sure to keep an eye on us slowpokes (while still giving us our space), and he was always supportive and gave positive support.
The food was great and impressive. (Hopefully you like potatoes, because you will get them for every meal!) The porters should be given a lot of credit for the amount thy carry. As a warning, make sure to book a porter when you book your trek, as they also need a permit. We didn't realize this, and the porters were fortunately able to add some of our things to their load, but I felt bad adding to their burden and would have preferred having a porter just for my sister's and my things.
I do recommend the trek, despite the challenge. Definitely give yourselves a few days to acclimate to the altitude. There are some awesome ruins that you can only see on the trek, and changes in environment were spectacular. It goes from a desert-like environment to a jungle.
It take preparation, but it is definitely worth it!.