great question. As a fellow skeptic I was apprehensive about these calls too.
One thing to note: how much can someone really tell you in 30-60 min?
They arent reading your essays and are going by mostly numbers.
Another thing is that its not in their best interest to lie. They would be exposed pretty quickly if they did (which has happened before!) and their business would be finished.
I think that advice is numbers based in the first interaction. if you meet certain targets (avg of gmat/gpa/we) then you should narrow down the schools yourself. Where a consultant comes in is helping you refine your story for impact and perhaps editing essays.
I spoke with 6 or 7 and they all had the same basic advice. I told them what schools I was interested in and the all pretty much agreed on which were stretches/within reach/safeties etc.
Talk to the rest and see for yourself. You could also post up your profile here to get some quick feedback.
If you write well I would read Rhymes guide to applying and do it myself.
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