yes, it will improve performance. not dramatically but it will. you already have 93. the biggest jump is from 91-96. 93 to 96 blend is not as big.
there's a huge difference on california 91 octane vs. half 100/half 91... low end torque improves a lot, as does smoothness when first starting off on a drive...
M3 Sedan - AW/Black - 6MT - no moonroof - no folding seats - RAC RG63 - clear bra by Omega Werks