I used Kaplan for the LSAT and it was well worth it. They have great resources. Keep in mind any prep course is what you make of it. If you do the work they give you, you'll benefit, if you slack until the last week and then cram....well.
Don't be put off by the price of kaplan, this is your future you're talking about, you've probably already shelled out 20-30k for UG and looking at another 30-50k for your MBA...what's another thousand bucks.
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