Hey I'm Josh I'm 20 years old this is my G5. So far I have a GM performance air intake, Pace Setter 4-1 headers, Magnaflow high flow cat, And GM performance cat back exhaust. Hopefully I can find a few more things for the engine here soon but so far I have not been able to find much. I also have 5% tint on all the windows except the windshield. I decided to keep the stock headunit for now but I have infiniti Kappa Perfect series 5 1/2" speakers in the doors and 6x9's in the deck. For a little thump in the trunk I have a 2000 watt SPL 2 channel amp powering 2 SPL 12 " woofers 700 watt RMS and 1800 watt peak on each. Also to add a little Conversation piece I have 2 locomotive horns in the grill powered by a 180psi compressor and a 2 liter tank. Just recently online I found a garett dual ball bearing turbo for the 05-06 G5's but I dont know if my ecu will handle it on the 07. I have submitted an email and I will find out soon:) Other then that any ?s just ask.. Hope you like it. Suggestions welcomed and other G5 owners let me know what you like or what you have .. Thanks for checkin out my ride.  Ok today is sept. 29th 2008 just an update for everyone.  I have added a new head unit to the car it is panasonic.. I love it so far.  Also i finally did a custom stereo installation. I have an orion Hcca 12.4  2000 watt rms and 4000 watt max.  in a custom built sealed box.. I also purchased a new amp which is working great..  It is an alpha sonic pmda 1200..  that thing kicks.  right now it is bridged to 2 ohms and pushin about 2000 watts to the sub..  I also added a kinetic audio cell to keep the lights from dimming while the base is thumping.  Other then that the car is good and rides really well since I wrapped it in goodyear rs-a rubbers..  I love these tires and they are a smooth ride.  Any question or comments let me know..