I looked into these adapters. I believe the best one to be the Brandmotion adaptor. It's plug & play, no wire splicing, uses the radio buttons to do all the functions. It looks super easy to install and when you push a button to do something, it reacts in 1/5 second. If I remember, they run like $160. That's the one I'm going with.
2006 GT Convertible - Screamin' Yellow, Black top & leather
87 octane Brenspeed tune
6000K, 35 W BiXenon HID headlights (Retro-Solutions)
5 Speed w/MGW shifter
Nitto 555 G2 tires