Yip this was an old discussion but difficult to achieve the same power as the 130i,
I had my 125i done but its no where near 130i power (haven't had Dyno done yet though) but Im very disappointed with results.
and fuel consumption is no different.
its not just me - there are many who have tried. the hardware might all look the same but there are slight differences. You will get rich if you know how to do it.
a follow up on this...there is a page on insta "the_workshop_dyno" they are doing a competition with bringing your car for power runs. a @qt_performance tuned 125i coupe did 143.5wkw and 263nm stage 1 pump fuel.