$300 - SCT X-Cal 3 with Brenspeed tunes for a 2005 - 2009 Mustang GT with a C&L Street Intake. Tunes come in 87, 89, and 93 octane, and are a VAST improvement over stock. If your vehicle is moded differently, or is a V6, Brenspeed, or any other tuner can create new tunes for you for a cost. Works with any 2005 - 2009 Mustang, and is not locked to the VIN on my vehicle. Can be bought with the below intake as a set for $550. Combined, they retail for ~$700.