Auto tuners do work but as Stroker pointed out if you do not put the time in then how do you know?? Or better yet what are you comparing it to. I hear all the time my bike runs great no issues, but really it is not tuned as well as it could be. Does that mean every bike needs to be re tuned ?? No just pointing out that many are not where they "could" be.
Auto tuners like the t max use wide band sensors. If you do not spend enough time in that cell it is not getting the best sample data. Do not blame the tool it only sees what it sees. How accurate is the sensor??? We use test gas on ours and I can tell you for fact that the sensors are throw away items. On avg I get 15-20 tunes out of a pair of sensor before they get very slow or just too far out of spec.
If you do not ride in a certain area due to what ever reason how can the system tune itself. I get plenty of t max units that need a fair amount of tweaking. Why because the owner of the system feed into the internet deal and thinks he is fine. If it is not checked it may or may not be plain and simple.
All systems have pros and cons,
Feedback can be false though due to the fact that many of the ex systems are not locating the 02 senors is the correct location or the bung is not allowing the sensor to get good readings at low ex flow. I see this often, customs installed the bung , it is too long or improperly located.
To compare one system to the next and stated that it does this or that better can be mis leading. If a system does not get good fuel milage, and the next does well that most likely not the system but the tune, or there lack of. OR maybe the new system is extremely lean at that given point or range . Who knows unless you check it.