X2. I have been real happy with the PLX SM-AFR. (I also have the DM-100 gauge). Accuracy has been excellent, always averaging 14.7 in closed loop, and hookup was very easy to the MPVI. The narrowband hookup was a little trickier, but still not bad. I use it as a more permanent solution, not to move from car to car.Originally Posted by viper04af