The device does what it says. It disables the AFM and takes away the hesitation and the sluggishness. I used to have a 2005 NBS Tahoe and I regretted exchanging it for a 2013 NNBS Tahoe due to the sluggishness caused by the AFM. Now I am enjoying the newer truck due to more responsive throttle. I did notice a loss of 0.5 MPG but it's worth it for the truck to not feel like a big slug.
Does not work with my car
I bought the stage1 because I thought having a K&N typhoon intake system and a Jet MAF sensor would be considered a minor modification, but when installed my car hesitates, cuts in and out and stalls! I am going to try exchanging for the stage 2 and see how that works! I've tried asking JET themselves but they won't answer me back!! So make sure if you buy the stage 1 your vehicle is stock!!
Save money and get more power, BUY THIS
I am up one mpg after one month of owning the range AFM disable and I also love the on demand power my Sierra was meant to put out. Not to mention this has also fixed a few hard shifting issues as well!! Thanks Range! Looks great too, has a cool looking blue light and looks very clean.