I have a Jon Lund 93 Octane Ghost Cam Tune on my car and it is awesome. Sounds and drives great. Not sure I would describe the sound as throaty, I would describe it as "lumpy". To put one of these tunes on your car you need to have a manual trans, and off-road x or h-pipe. They won't sell you one if you have an automatic or have the cats on your car.
This link is to a video I made last winter of my car after I put the tune on it. You can get an idea how it sounds- the Ghost Cam effect only "kicks in" at idle. Keep in mind that it was below 30 degrees that day, so that is not smoke you see coming out my exhaust.
2011 GT M6 Premium- Mechanical upgrades include: Boss 302 Intake, JLT CAI, JPC LT Headers, Off Road X Pipe, and mufflers, 410 Gears, Granatelli Hot Street Coil Packs, 93 Octane Ghost Cam Tune by Jon Lund,Eibach ProKit Springs,shocks, struts and sway bars, BMR LCA's, Strut Tower Brace, and adjustable Panhard Bar, Maximum Motorsports Camber/Caster Plates, Barton Shortshifter and bracket, Wilwood Superlight Brakes w/6 and 4 piston calipers, Steeda Spyders- 9-1/2X20 with 275/35 and 11X20 with 315/35 Nitto Invos.