For one thing, N54 (and N55) engines use DIRECT INJECTION, which implies piezo-electric devices for extremely high fuel pressures directly into the combustion chamber, not into the intake manifold as with the non-turbo N52 engine (as an example). Holley, while famous for carburetion and other fuel-system related parts in the American car market, likely does not make piezo injectors that will work with a BMW engine. Note that every one of those parts listings says "universal" and not car-specific. While they may be similar, I certainly wouldn't put "universal" injectors in my $16K German engine. For one thing, replacing injectors requires "coding" them according to the numbers on the injector body, and it's highly unlikely that these would work at all, let alone give you any kind of performance advantage. Bosch, on the other hand, would be where you'd want to look, but they're not going to be cheap.
2013 F30 335i M-Sport 8AT/MPE/MPPK, 2011 128i M-sport Cabrio 6MT/PE