:I think that this is fair enough if two criteria are satisfied- 
 :1) That quotes are not used as a means unto themselves, rather that they are used to support a point that is being made. If you only include favourable quotes, it reads like spam/infomercial/tv shopping, and undermines reader confidence in the thing that is being advocated. 
 :2) That all quotes are referenced, preferably to an online source. (this is a wikipedia requirement) 

 :In other words- by all means have a praise section, but do not make it a list of spammy testimonial (although you could of course include a referenced quote to back up a point that you are making). Maybe the 'Praise' section could more appropriately be called something like 'The Strengths of Waldorf Education'. 
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