Hey all, new to the forums here, so bear with me. If this has been addressed elsewhere, please direct me!

First, I have been wading through the mountain of PDC offerings around, going through webpage after webpage after webpage after...., and am wondering if there is any website/platform that offers independent review/feedback of PDC's. Everyone has the glowing testimonials on their sites....but there are PDC's and then there PDC's....

I am thinking something akin to amazons or ebay's user based review/rating system, or one that does a "compare-contrast/pro-con" of whats out there....or even just a PDC clearing house with user feedback.

Does such a thing exist? If not, what would it take to start it? Is that feasible? ....or are we just stuck trusting self-posted testimonials and old-school style word of mouth?
It would seem to me that the exposure would motivate folks offering PDC's to participate.

The closest thing that I've found is by wethetrees, which is fantastic, but very limited in volume, and has no user-input functions.

Second, at the moment I am trying to find my first PDC, and to sift through my options, thus I am interested in feedback on a couple programs in particular:

http://vergepermaculture.ca/
http://wholesystemsdesign.com/
http://www.quailsprings.org/programs/permaculture/
http://www.spiralridgepermaculture.com/permaculture-design-course/

Reviews/thoughts? How do these rank in the world of PDC's? Should I spend my money elsewhere? And why?

Thanks for your thoughts!
Sylvia