This looks pretty interesting. I'll be checking it out.
However, I'm having an issue with the idea that it would replace private lessons... Nothing, NOTHING can replace an experienced and trained ear listening to you...
I don't think it would replace private lessons, this is completely not the aim,
however i do believe that it would allow you to make better use of your private lessons.
You will be able to practice in an easier way, work on your weak areas faster and advance faster in your lessons.