Jet Performance Chips Power Control Module (PCM)

I want to get the Jet Performance Chip Power Control Module-Stage 1 for my 1997 GMC Safari. I heard that lots of people are saying that it is really good for gaining more horsepower, getting better shifts, and it also helps you save fuel. Is it true?

You can find it at: http://www.autoanything.com/products/product_gnn.aspx?se=jet_performance_chips_power_co ntrol_module_pcm&p_id=1777

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