AFR Gauges

I use one... AEM is what I have. I know I'll get blasted for this, but it is much easier for me to tune the car than reading plugs. I look for mid to low 14.0 for idle and cruise which is what I have and at WOT, I want at least in the mid 12.0 range to be safe and then tune from there. ALL newer cars use O2 sensors to run their programming so how wrong can I be... Puts on Kevlar/Nomex shirt...