The Salkantay trek was a very powerful experience, both mentally and physically. We have seen the top of Salkantay at 4600m which is absolutely beautiful. We have also seen jungle, villages and even slept at a farm! The scenes were beyond magic, I will dream for months about them.
The guide and the cooks were doing an excellent job: extra information, always helpful and the food was the best I have seen in peru. I have to say for the money we paid the first breakfast could have been included. We did the zip lining (not included) which is magic but we had to skip some of the trail for that, I rather hay done this instead of the hot springs.
I would advise buying your own walking poles in cusco, it's a must have.
Also advisable is good (Thermo) clothes and shoes. Rent is more expensive than buying. This trek is not easy, but if you are fit you should do it: once in a lifetime experience !!!.