We actually see a few folks pairing the MGMAT books
with a Knewton course.
I have not taken either, so I can't vouch for one or the other but one thought that comes to mind, Knewton does give a 50 point money back guarantee.
P.S. If you end up picking Knewton, you can start with the On-Demand course and then if you feel that you need more in-class interaction, you can upgrade to the full class (just email them).
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