Both are equal for the power gain, which is not alot.
The magnaflow could sound better because of resonator delete.
128i Sport 6MT converted to Euro 130i spec, tuned by EVOLVE
In-progress: Evolve tune configuration!!; custom lip, some susp.
"The 1-series is the last car that BMW engineered before the Germans, as a car-making culture, fell out of love with driving." - R&T 2013 135is Review