I have recently completed the Photography institute Diploma.
Good points: made me use my cameras facilities better as when I came across something in course I went looking for more information online. I have a much better understanding of my camera and how to use it.
Negative points: having completed the course I feel that it is expensive for what it is. The text should keep your interest all the way though; although reasonable writing style did find it hard not to wander off sometimes. Feedback from tutors on assignments are often very generic answers with minimal personal input. If you want more you have to push for it. Assignments were a bit boring in the main. The last one being a self assessment which was such a let down for a last assignment as it was not marked so you were left with a "was that it" feeling.
All in all if I had my money to spend again I would use it very differently. If all you want is the diploma to hang on your wall fine but if you want some challenging where you feel you have really achieved something. do something else!
In summary, I would not recommend The Photography Institute to a friend.