Firstly THEY ARE FOOKIN AWESOME, i had one on my black gt and was by far the best mod i did to it. socks has one on his glanza and mickey boy sings there praises too Basically luke they dont "self-learn" as such but everytime you change something or modify something it will adapt to the new mod accordingly and change things. so some do say it self learns which i can see why they do but its actually just adapting to the new mod Good things about them? they eliminate fuel cut, take away the speed limit (112mph) restriction, provide better acceleration, better mid-range torque and give you that little bit more kick at top end. amazing little ECU's you'll love it